Conveyor package flow density adjustment system

Abstract

A method and apparatus for detecting and detecting parcel flow density on selected sections of a supply conveyor and a receiving conveyor, and for controlling parcel flow density by adjusting the conveyor speed. The conveyor includes a distance-sensing field to be measured at a selected position. The distance-sensing device includes a virtual encoder and signal-generating and detection means extending across the surface of the conveyor. A computer calculates a desired occupancy percentage for the receiving conveyor and the actual occupancy percentage for the receiving conveyor. A programmable logic control unit controls the conveyor speed and start / stop operation of the supply conveyor and the receiving conveyor based on signals received from the distance-sensing device to optimally position packages on the supply conveyor or the receiving conveyor.

Description

Technical Field

[0001] (Cross - reference to related applications) This application claims priority from U.S. Provisional Application No. 63526735, filed on July 14, 2023, which is hereby incorporated by reference in its entirety.

[0002] The present invention relates to the field of detecting and controlling the parcel flow density on a conveyor by adjusting the supply conveyor speed and the receive conveyor speed using different sensing and detection methods, optimizing the flow density, and managing, tracking, and integrating the bulk flow.

Background Art

[0003] Conveyor systems often function to align and space the articles on the conveyor system that are processed by a downstream sorting system. Conventional conveyor systems generally involve controlling the articles such that the articles exiting the guiding subsystem have gaps between them or beside them that are close to a desired length. The desired gap may be variable depending on the length and / or width of one or more of the pair of articles that define the gap, or the desired gap may be constant. Regardless of the criteria used to determine the length of the desired gap, the gap serves the purpose of facilitating the sorting of the articles. Sorting systems often function more effectively when there is a certain minimum spacing between the articles being sorted. However, gaps that exceed this minimum generally reduce the throughput of the conveyor system. While it is desirable to create a gap that balances the sorting criteria while maximizing throughput to the sorting and singulator devices, at the induction points where parcels are fed onto multiple conveyors from various supply points such as the unloading stations of trucks, maximum efficiency is achieved by moving as many parcels as possible over a given area of the conveyor.

[0004] Variations in the volume of products entering from various supply belts create imbalances in various merge areas of the conveying system, resulting in large open spots in the collection belt, singulator belt, and sorting area. This leads to inefficiency, unnecessary capital investment, and reduced overall sorter throughput. Conventional flow control systems count packages and / or control the conveyor speed to orient or unify packages and create the minimum gaps necessary for processing. Examples of these devices are described in the following patents and / or publications.

[0005] U.S. Patent No. 5,165,520 teaches a conveying system that includes a camera system that arranges parcels on a belt, recognizes parcel overlaps and congestion, and bypasses problematic parcels. U.S. Patent No. 8,061,506 teaches merging articles on a conveyor using information collected from optical sensors or cameras, disclosing that it recognizes or creates gaps on the collection belt and fills these gaps with packages from the supply belt. However, Schafer does not discuss how to process information from cameras or optical sensors to control the concentration of packages. Publication No. 5,165,520 teaches a conveying system that uses cameras to determine the number of parcels and uses this information to control the speed of conveyors such as parcel supply conveyors, acceleration conveyors, buffer conveyors, singulators, and transport conveyors. However, this document does not teach or suggest the idea of ​​controlling the conveying speed to maximize the area covered on the conveyor as a function of the occupancy on the collector or immediately before the singulator. U.S. Patent No. 6471044 teaches that an image is transmitted to a control system where the image is interpreted to determine the number of packages and the average size of the packages, and to adjust the speed of a parcel supply conveyor, buffer conveyor, acceleration conveyor, singulator, and transport conveyor, but does not teach the adjustment of the density of parcels on a given area of ​​the conveyor. U.S. Patent No. 5141097 teaches analyzing an image supplied from a camera to provide an index indicating the number of packages present in this image and to increase the conveyor speed to obtain a desired throughput. U.S. Patent No. 6401936 teaches a sensing system for monitoring the flow rate of articles and for use with a singulator downstream of a coarse singulator, hold-and-release conveyor, or strip conveyor to identify and / or track individual articles passing through the system, and a control system is used in conjunction with the sensing system to adjust the flow rate of articles passing through the system by increasing the conveyor speed.

[0006] Conventional systems have relied on counting carton feet or parcels unloaded from container unload conveyors and adjusting the conveyor speed to maintain a manageable input flow rate for singulators and sorters. The goal is to keep the system supplied without oversupplying. Current parcel handling systems have a sorting capacity of 12,150 parcels per hour (pph) at 540 feet per minute (fpm) with a 12-inch gap and an average of 20 inches. As a result, the system's throughput efficiency is limited, and the sustained performance capability is expected to be only about 60% of the sorting capacity. A control system is needed to maximize the occupancy and density of packages in a given area of ​​the receiving conveyor where packages are unloaded, and a mechanism is required to sense the physical characteristics of packages from means of transport such as railcars, airplanes, ships, or trucks and control the transfer speed of the goods to send them to the appropriate sorting system. [Overview of the Initiative]

[0007] This application is an improvement on the invention described in Applicant's International Application No. PCT / US2020 / 042429, filed on 16 July 2020, and the corresponding U.S. Patent No. 11459188, published on 4 October 2022, “A distance sensing device and method for measuring and controlling the density of parcels on a conveyor,” which are incorporated herein by reference. This relates to a field in which parcel flow density on selected sections of supply and receiving conveyors is determined as a one-dimensional linear, two-dimensional area, or three-dimensional volume using various sensing and detection methods, and to a field in which parcel density or volume in a selected area of ​​a receiving conveyor is increased by adjusting the conveyor speed ratio proportional to the ratio of a desired density to the current density. Using various sensing and detection methods, the parcel flow density on selected sections of the supply and receiving conveyors is determined as a one-dimensional linear, two-dimensional area, or three-dimensional volume. The conveyor speed ratio is then adjusted, proportional to the ratio of the desired density to the current density, to increase the density or volume of parcels (typically a mixture of box-shaped parcels with dimensions ranging from 6 to 60 inches) in the selected area of ​​the receiving conveyor, and further control the bulk two-dimensional parcel flow to the singulator, providing sustained throughput with higher singulation accuracy.

[0008] The present invention improves upon the concept by measuring the bulk flow density approaching the transfer between conveyors, using distance sensors mounted on both sides of the upstream conveyor ahead of the transition, and recording distance values ​​at the belt travel interval. Based on the encoder input, the area utilization rate over a predetermined length of the conveyor is calculated by numerical integration. The velocity based on the flow density of the collection line can be calculated as it approaches the merge area, and the flow rate from the supply conveyor is limited based on the available area of ​​the collection line. When a bulk parcel flow is transferred between two conveyors operating at different speeds, the parcel flow density (conveyor area utilization rate or occupancy rate) before and after the transition is proportional to the speed ratio between the conveyors.

[0009] This invention uses distance sensors to measure the flow density approaching a transfer section between conveyors. This is a form of numerical integration. Distance sensors are mounted on both sides of the upstream conveyor ahead of the transfer section, and distance values ​​are recorded at belt travel intervals based on encoder inputs with a predetermined resolution (2 inches in Figure 4). These values ​​are recorded in an array and used to determine area utilization on a conveyor of a predetermined length.

[0010] Flow density adjustments in the series of conveyor transitions, dock unloading conveyors, and primary sort collectors on the collection line leading to the singulator are all subject to control by the flow density adjustment method. This method can be used to widen and narrow parcel spacing at various points within the conveyor system and to determine appropriate conveyor speed ratios. At the transition points of the butt merge, a method can be used to periodically stop the merge conveyor to avoid jamming.

[0011] The present invention specifies a distance sensing device for measuring and controlling the density of articles on a conveyor, comprising or consisting of a supply conveyor, a butt-merge conveyor, and a receiving conveyor, each conveyor having an independent variable-speed drive motor. The supply conveyor includes a range sensing field of measurement at its distal discharge end adjacent to the receiving conveyor. The receiving conveyor includes a range sensing field of measurement at its receiving end adjacent to or near the discharge end of the supply conveyor. The butt-merge conveyor includes a range sensing field of measurement at its distal discharge end adjacent to the receiving conveyor, after the range sensing field of measurement of the supply conveyor and before the range sensing field of measurement of the receiving conveyor. A distance sensing device having a virtual encoder and signal generation and detection means extends across the entire surface of the measurement areas of the supply conveyor, the butt-merge conveyor, and the receiving conveyor. The computer calculates the desired occupancy percentage of the receiving conveyor and the actual occupancy percentage of the receiving conveyor. The programmable logic control unit controls the conveyor speed and start / stop operations of the supply conveyor and butt merge conveyor based on signals received from distance sensing detectors that identify gaps between packages on the receiving conveyor that are sufficient space to insert additional items from the supply conveyor and butt merge conveyor.

[0012] This system applies density measuring devices and conveyor speed control to the conveyor system to adjust the flow rate of bulk items or parcels to the singulator, providing higher sustained throughput with higher singulation accuracy. When the system is filling up, the collection conveyor becomes an active buffer, compressing the flow density to fill the collection line to the desired target fullness. Voids and areas with low flow rates are pulled forward and compressed to the target fullness. Areas that are clumped or overpacked are thinned out to reduce the possibility of jams downstream.

[0013] Generally, the optimal bulk parcel flow supplied to a singulator is such that the conveyor area utilization rate is no less than 15% and no more than 40% relative to the 50-foot belt length of the flow entering the singulator. The actual required high, low, and average speeds should be determined based on the conveyor system throughput limits, average parcel size, and average flow density range.

[0014] This is an improved method that utilizes a series of sensors to collect multiple measurements of packages moving along a supply conveyor and a collection conveyor, stores and analyzes the multiple measurements in software to determine the area utilization rate over a given length of the conveyor, and uses a programmable logic control device to variably control the speed of the supply conveyor and the collection conveyor to achieve a desired percentage area utilization rate or desired occupancy percentage of packages on the supply conveyor or the collection conveyor. The series of sensors includes at least one vision sensor positioned above the conveyor, or at least two vision sensors positioned on opposing sides of the conveyor. The series of sensors is selected from distance sensors such as ultrasonic sensors, infrared proximity sensors, light detection and ranging (LIDAR) sensors, or vertical-cavity surface-emitting laser (VCSEL) sensors. The supply conveyor is driven by a variable-speed motor networked to a programmable logic control unit, which adjusts the conveyor speed to the required speed calculated between the minimum and maximum speeds, so that the supply conveyor merges parcels with the collection conveyor at the appropriate time to reach the desired occupancy percentage. The programmable logic control unit stops the supply conveyor when the calculated conveyor speed falls below the minimum speed and restarts the conveyor when the calculated required speed exceeds 110% of the preset minimum speed. The supply conveyor is driven by a single-speed motor networked to a programmable logic control unit, which starts and stops the supply conveyor at appropriate intervals so that the desired percentage area utilization rate is achieved when merging with the collection conveyor. The supply conveyor stops when the calculated speed falls below the minimum speed and restarts when the calculated required speed exceeds 110% of the preset minimum conveyor speed.A method for optimizing the flow density of packages on the collection conveyor is achieved by variably adjusting the speed of the supply conveyor. The adjusted supply conveyor speed can be calculated by multiplying the ratio of the desired occupancy percentage of the supply conveyor to the actual occupancy percentage of the supply conveyor by the speed of the collection conveyor. The actual occupancy percentage of the supply conveyor is determined by the numerical integration of a pair of distances measured at regular intervals by a series of opposing distance sensors as the package moves along the supply conveyor upstream of the junction with the collection conveyor. The regular interval is determined by a physical encoder input with a predetermined resolution attached to the conveyor, or by a virtual encoder input. The speed of the supply conveyor is controlled so that the percentage area utilization rate of the collection conveyor is not less than 15% and not more than 40%. The supply conveyor speed is 0.05G (0.5m / s). 2 It can accelerate and decelerate at speeds below the following limits.

[0015] The density measuring device recognizes and maximizes the area utilization rate of the conveyor surface. The sensing and detection device determines the parcel flow density on a selected area of ​​the conveyor as a one-dimensional linear, two-dimensional area, or three-dimensional volume, and improves the performance and throughput of the conveyor system by increasing the density or volume of parcels in the selected area by adjusting the supply and receiving conveyor speed ratio, which is proportional to the ratio of the desired density to the current density. The sensing and / or detection device is placed at the flow inlet or transition points between the supply and receiving conveyors. The control algorithm recognizes the area, volume, or density of individual objects and the ratio of the speed or velocity at which individual objects pass through in the selected area of ​​the supply and receiving conveyor surfaces, and recognizes the area utilization rate of the supply and receiving conveyors to maintain the desired density of packages on the receiving conveyor surface.

[0016] The bulk parcel flow management system includes, or is configured with, a density-based detection system that recognizes belt area utilization and parcel count. System density detection devices are located at the flow inlet and singularity. The control algorithm requires recognition of individual objects and their pass rates, as well as the area utilization of the collection belt. Average parcel size (area or volume), including length, width, and height, may also be considered. Furthermore, density, defined as parcel (area, volume, or weight), can be considered in relation to the area utilization of the conveyor surface. The conveyor package management system may also identify, locate, or track packages, parcels, or other objects on the conveyor by digital images, scanner codes, or footprints.

[0017] To achieve optimal performance, the system recommends equipping all bulk supply conveyors leading to the singulator with variable-speed drives networked to the singulator's process logic control (PLC), and receiving the speed determined by the fill algorithm at intervals of 50 milliseconds or less.

[0018] Furthermore, key functional characteristics to be considered when the system is filled include: the collection conveyor acting as an active buffer to compress the flow density and fill the collection line to the desired target level; voids and areas with low flow rates being pulled forward and compressed to the target level; and clumps or overpacked areas being thinned out to reduce the possibility of jams downstream.

[0019] A device for detecting and measuring the density of parcels on a selected section of a conveying surface comprises, or is configured thereof, multiple photoeyes for generating a table of sensing ranges. Each photoeye has two outputs, each independently adjustable to obtain two different ranges. The multiple photoeyes are installed on a first side of the supply conveyor and a second side opposite the selected section, the supply conveyor having a conveying surface extending to the receiving conveyor, and the receiving conveyor having a conveying surface at a selected distance from the discharge end of the supply conveyor and the receiving end of the receiving conveyor. A virtual encoder is programmable to generate pulses at selected intervals on the supply conveyor. An array comprises multiple array elements, each of which represents one pulse of the virtual encoder defining a selected length of the selected distance. A programmable logic controller has an algorithm for calculating the average measured occupancy of the array, which represents the occupancy rate of the receiving conveyor.

[0020] A method for detecting and measuring the density of parcels on a selected section of a conveying surface includes the step of generating a table of sensing ranges using multiple photoeyes. Each photoeye has two outputs, each independently adjustable to obtain two different ranges. The multiple photoeyes are installed on the first side of the supply and receiving conveyors and the second side opposite the selected section, at a selected distance from the discharge end of the supply conveyor and the receiving end of the receiving conveyor. A programmable virtual encoder generates pulses at selected intervals along the selected section of the conveying surface. An array is formed containing multiple array elements, each of which represents one pulse of the virtual encoder defining a selected length of the selected distance. By determining the combination of photoeye outputs blocked when an encoder pulse occurs, a programmable logic control unit using an algorithm calculates the average measured occupancy of the array, which represents the percentage of the receiving conveyor's occupancy. The measured occupancy of the receiving conveyor is compared to the desired occupancy of the supply conveyor. The speed ratio is the desired occupancy divided by the measured occupancy. The speed of the supply conveyor, the speed of the receiving conveyor, or the speeds of both the supply and receiving conveyors are adjusted to obtain a desired occupancy rate on the receiving conveyor.

[0021] In addition to distance-sensing photoeyes, the sensors may include opposing or left / right distance-sensing photoeyes, vibration sensors, thermal sensors, weight sensors, cameras, and smart light stacks that communicate with a PLC or computer.

[0022] Multiple first packages from the first supply conveyor and multiple second packages from the second supply conveyor are merged into an intermediate flow control conveyor and supplied to a collection conveyor. Here, the area utilization rate of the first supply conveyor is determined by a series of distance sensors located upstream of the junction between the first supply conveyor and the intermediate flow control conveyor. The area utilization rate of the intermediate flow control conveyor is determined by a series of distance sensors installed upstream of the junction between the intermediate flow control conveyor and the collection conveyor. First packages from the first supply conveyor are dynamically supplied to the intermediate flow control conveyor by variably adjusting the speed of the first supply conveyor to achieve a first desired percentage area utilization rate of the intermediate flow control conveyor, which is sufficient for the second packages from the second supply conveyor to merge into the intermediate flow control conveyor. The speed of the intermediate flow control conveyor is adjusted to achieve a second desired percentage area utilization rate of the collection conveyor. The area utilization rate of the second supply conveyor is also determined by a series of distance sensors installed upstream of the junction between the second supply conveyor and the intermediate flow control conveyor, and a first desired percentage area utilization rate of the intermediate flow control conveyor can be achieved by changing the speed of either the first or second supply conveyor. The first supply conveyor is positioned linearly with the intermediate flow control conveyor, and the second supply conveyor is butt-merged perpendicularly to the intermediate flow control conveyor. The first and second supply conveyors are in contact perpendicularly with the intermediate flow control conveyor.

[0023] The objective of the present invention is to track the speed provided by a singulator program logic controller (PLC) within 5% of the speed provided by the PLC.

[0024] The objective of this invention is to limit high speed to 350 feet per minute (fpm) and low speed to 100 feet per minute, with an average speed of 225 feet per minute as the target.

[0025] The object of the present invention is that the supply conveyor accelerates and decelerates at a rate of about 0.05G (0.5 m / s 2 ), avoiding the need for dynamic braking and reverse torque of the drive train.

[0026] The object of the present invention is to provide a distance-sensing conveyor package management system that includes photo eyes for monitoring packages in the merge area of the supply conveyor across the collection conveyor, singulator conveyor, and sorter, identifying areas of low density, and controlling the startup and speed of the selected conveyor to increase or decrease the density of articles in a given area of the conveyor.

[0027] The object of the present invention is to provide a distance-sensing conveyor package management system that utilizes algorithms and software within a computer to calculate the empty or unused area on a conveyor by comparing the area covered by packages and the empty area on the conveyor based on digital data analysis of information from each of the photo eyes monitoring the conveyor.

[0028] The object of the present invention is to provide a distance-sensing conveyor package management system in which the photo eyes interface with a computer that assembles data from the photo eyes and outputs speed signals to selected supply and collection conveyors within the system, filling or spacing parcels in areas on the collection conveyor to achieve a selected density in a specific area.

[0029] A distance-sensing conveyor package management system that determines the percentage of the surface area of a collection conveyor, singulator conveyor, and other conveyors that is covered by packages, parcels, bags, envelopes, boxes, or other articles.

[0030] A distance-sensing conveyor package management system that counts and identifies the number of items contained on a conveyor.

[0031] A distance-sensing conveyor package management system can locate packages and identify packages, parcels, or other items on a conveyor by digital image or footprint.

[0032] The distance-sensing conveyor package management system allows for the adjustment of conveyor speeds in a system where photo-eyes or other detection means are positioned at each supply source to the conveyor, controlling the speed of each supply conveyor and the speed of the collection conveyor to maximize the flow rate of packages through the system.

[0033] The distance-sensing conveyor package management system forces packages to move to one side of the collection conveyor via friction, inclined rollers, belts, or inclined surfaces, causing the subsequent supply conveyor to add packages to empty spaces next to packages already present on the collection conveyor.

[0034] The distance-sensing conveyor package management system recognizes the number of objects, the average size of the objects, and the conveyor area utilization rate.

[0035] A system based on a distance-sensing photoeye array can be used to regulate the input flow rate to a conveyor system, with the photoeyes positioned at each source of the input flow rate, allowing for control of each input with respect to the maximum allowable input flow rate to the system.

[0036] A system based on a distance-sensing photo-eye array can recognize the number of objects, the average size of the objects, and the area utilization rate of the conveyor.

[0037] The distance detection system can determine the occupancy level of the accumulation area of ​​the conveyor system, and more specifically, the occupancy level of the parcel singulator.

[0038] A virtual or physical encoder for generating pulses to trigger the acquisition (capture) of distance values.

[0039] A flow control system based on a distance-sensing photoeye array may include photoeyes, a computer processor, and interfaces, and can define, control, and integrate a conveyor control system via Ethernet, Wi-Fi, Bluetooth, and smart electronic devices such as visual aid computer-based devices that can communicate with telephones, tablets, laptop computers, and other computer systems.

[0040] Using different detection and detection methods, the parcel flow density on selected sections of supply and receiving conveyors can be determined as a one-dimensional linear, two-dimensional area, or three-dimensional volume. By adjusting the conveyor speed ratio, which is proportional to the ratio of the desired density to the current density, the parcel density or volume in the selected area of ​​the receiving conveyor can be increased.

[0041] This distance sensing system can be used in combination with a photo-eye based bulk parcel flow management system method, the method comprising the steps of selecting a transition zone between a supply conveyor and a receiving conveyor, each having an independent drive motor; selecting a photo-eye field of view of the selected transition zone; assigning an IP address to each photo-eye; and setting an in-line supply conveyor speed to achieve a desired conveyor area utilization rate on the downstream receiving conveyor, where V is the speed (conveyor speed), DO is the desired occupancy rate, RCO is the receiving conveyor occupancy rate, FCO is the supply conveyor occupancy rate, and the occupancy rate is the conveyor The process includes, or comprises, the steps of: indicating the area (including conveyor area, conveyor volume, or conveyor density); selecting a percentage of the photoeye field of view; selecting a percentage of the supply conveyor occupancy definition zone; selecting a percentage of the receiving conveyor occupancy definition zone; selecting a percentage of the desired occupancy after merging; supplying parcels to the receiving conveyor occupancy definition zone; transporting parcels toward the zone of the desired occupancy at a selected location; and merging parcels at the transition between the supply conveyor and the receiving conveyor.

[0042] Apparatus and methods used for transporting parcels and controlling the speed and direction of parcels on a conveyor are disclosed in the applicant's U.S. Patent Nos. 1,0427884 and 1,0773897, which are incorporated herein by reference, and which disclose camera-based vision density management systems. The present invention provides a method for measuring parcel density and parcel position based on a distance-sensing photoeye as an alternative to a camera.

[0043] Other objects, features, and advantages of the present invention will become apparent from the following detailed description, used in conjunction with the accompanying drawings.

[0044] The following description, when viewed in conjunction with the attached drawings, will provide a deeper understanding of the present invention. Throughout the drawings, the same numbers indicate the same parts. [Brief explanation of the drawing]

[0045] [Figure 1] This is a top view of the conveying surface, where opposing distance-sensing photoeyes are installed at selected intervals on both sides of the conveyor section near the exit end to create a table of sensing or detection ranges. [Figure 2] This diagram illustrates a density measurement method that uses distance-sensing photoeyes to output the actual analog distance. Using an analog output sensor, the true distance from the end of the belt to the sensed parcel is known, and distance-sensing photoeyes on both sides of the belt are used to neutralize the influence of parcels shifted to one side. [Figure 3] Diagram showing the architecture of an area-use IO-Link based distance-sensing photoeye. [Figure 4] This diagram shows a conveyor section with various parcels of different shapes and sizes passing through multiple encoder pulse positions, where the right photo eye (PER) position is opposite the left photo eye (PEL) position, the conveyor is 60 inches wide, and the 120-inch long segments are divided into measurements at 2-inch intervals as shown in the array. [Figure 5] This diagram shows a two-dimensional series of conveyor systems, including a supply conveyor and a receiving conveyor, illustrating that roller or belt conveyors use independent motors to transport, position, and separate parcels, and that the system controls the number of parcels using the principle of conveyor area utilization and distance-sensing photoeyes positioned at the inlet points of selected conveyor flows, enabling efficient supply to the receiving conveyor. [Figure 6]This diagram illustrates a two-dimensional supply and collection conveyor application showing the merging of an intersecting collection conveyor and a side transfer supply conveyor, demonstrating that the conveyor speed ratio is set to achieve a desired conveyor area utilization rate in the downstream portion of the collection conveyor based on a distance-sensing photo-eye system at the intersection, which is based on the occupancy rate of the receiving conveyor. [Figure 7] A perspective view illustrating the distance-sensing-based conveyor package management system of the present invention, showing the distance-sensing photo-eye field of view of the bulk parcel flow management system, and indicating that the in-line conveyor speed is set to achieve a desired conveyor area utilization rate on the downstream conveyor including the singulator. [Figure 8] This schematic diagram illustrates a distance-sensing density flow control system applied to a bulk supply system from a trailer dock to a sorter, including a control system that adjusts multiple individual inputs based on the fullness of the conveyor and singulator at various locations, showing that the conveyor speed is adjusted as a function of the singulator's fullness and inflow occupancy rate. [Figure 9] Top view showing a camera-sensing parcel flow control system, including a circulation loop, from the trailer unloading supply conveyor through the singulator. [Figure 10] This diagram shows a supply conveyor merging with a collection conveyor that has modular sections, with photo-eye distance sensing arrays positioned at the intersection of each conveyor. [Figure 11] Top view of a conveyor assembly showing packages moving forward on a supply conveyor parallel to a collection conveyor. [Figure 12] Figure 11 is a top view showing packages moving forward on a supply conveyor parallel to a collection conveyor, with a portion of the collection conveyor controlled to ensure space for receiving items transported by the supply conveyor. [Figure 13]Figure 11 is a top view showing packages moving forward on a supply conveyor parallel to a collection conveyor, indicating that the items transported by the supply conveyor are positioned in the receiving section of the collection conveyor. [Figure 14] Figure 11 is a top view showing packages moving forward on a supply conveyor parallel to a collection conveyor, illustrating that items transported by the supply conveyor are supplied to a position ahead of multiple items transported on the collection conveyor. [Figure 15] Figure 11 is a top view showing multiple packages moving forward on a collection conveyor, illustrating that an inclined feed conveyor and a lateral feed conveyor are controlled to insert packages into the empty areas of the collection conveyor. [Figure 16a] A top view of a conveyor with two ends connected and traveling at different speeds, showing the low-density state of parcels before and after the application of speed control to the supply conveyor. [Figure 16b] A top view of a conveyor with two ends connected and traveling at different speeds, showing the low-density state of parcels before and after the application of speed control to the supply conveyor. [Figure 17] A diagram showing a distance sensor for measuring the flow density of parcels approaching the transfer between the supply conveyor and the receiving conveyor. [Figure 18] This diagram illustrates an example of binary start-stop control in a butt merge conveying system, showing that the supply conveyor is stopped to prevent jamming with parcels from a second supply conveyor that is perpendicularly adjacent to the collection receiving conveyor. [Figure 19] This diagram illustrates an example of a butt merge conveyor that combines and tracks bulk flow transfers from different conveyors operating at different speeds. [Figure 20] This diagram illustrates an example of a butt merge conveyor that tracks and combines bulk flow transfers from transverse conveyors operating at different speeds. [Modes for carrying out the invention]

[0046] According to the present invention, a distance-sensing parcel flow management system is provided that uses different sensing and detection methods to determine the parcel flow density as a one-dimensional linear, two-dimensional area, or three-dimensional volume in selected sections of a supply conveyor and a receiving conveyor, and increases the parcel density or volume in a selected area of ​​the receiving conveyor by adjusting the ratio of the conveyor speed which is proportional to the ratio of the desired density to the current density.

[0047] The terms used herein are for illustrative purposes only and are not intended to limit any particular exemplary embodiment. In this specification, the singular forms “a,” “an,” and “the” may also be intended to include the plural form unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having” are inclusive and identify the presence of the described features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. The method steps, processes, and operations described herein should not be construed as necessarily having to be performed in a specific order discussed or illustrated unless specifically identified as such. It will also be understood that additional or alternative steps may be employed.

[0048] When an element or layer is described as “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged to, connected to, or coupled to the other element or layer, or there may be an intervening element or layer. In contrast, when an element is described as “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening element or layer. Other words used to describe relationships between elements should be interpreted similarly (e.g., “between” and “directly between,” “adjacent” and “directly adjacent”). As used herein, the term “and / or” includes any combination of one or more of the enumerated items relating to it.

[0049] In this specification, terms such as first, second, third, etc., may be used to describe various elements, components, regions, layers, and / or sections, but these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms can be used only to distinguish one element, component, region, layer, or section from another region, layer, or section. As used herein, “first,” “second,” and other numerical terms do not imply order or sequence unless explicitly indicated by the context. Accordingly, without departing from the teaching of the exemplary embodiments, a first element, component, region, layer, or section described below may be referred to as a second element, component, region, layer, or section.

[0050] In this specification, spatially relative terms such as “inner,” “outer,” “beneath,” “below,” “above,” and “upper” may be used to describe the relationship between one element or feature and another, as shown in the diagrams, for the sake of clarity. Spatially relative terms may be intended to encompass different orientations of the device during use or operation, in addition to the orientation shown in the diagrams. For example, if the device in the diagram is turned over, an element described as “beneath” or “below” of another element or feature will face “above” of that other element or feature. Thus, the illustrative term “below” can encompass both up and down orientations. The device may also be in other orientations (a 90-degree rotation or other orientations), and the spatially relative descriptors used herein shall be interpreted accordingly.

[0051] As used herein, the term “about” can be reasonably understood by those skilled in the art to mean a range of ±10% from the stated value, either slightly above or slightly below.

[0052] As used herein, the terms “parcel flow density adjustment” and “package flow density adjustment” are equivalent.

[0053] As used herein, the terms “parcel and article” are used synonymously and include articles, envelopes, mail, packages, bags, drums, boxes, or irregularly shaped articles or transport containers.

[0054] As used herein, the term “range sensing” includes one or more imaging devices, including photoeyes, cameras, video photoeyes, scanners, lasers, selected light transmission frequency or wavelength or radiation detectors, or other pixel detection devices and / or digital imaging devices (collectively referred to as photoeyes).

[0055] The present invention will be described in more detail below with reference to the accompanying drawings illustrating preferred embodiments of the invention. However, the present invention may be carried out in many different forms and should not be construed as being limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure may be thorough and complete and so as to convey the scope of the invention to those skilled in the art. Throughout, the same numbers refer to the same elements.

[0056] According to the present invention, a parcel flow management system is provided that is based on a density-based distance sensing detection system that recognizes belt area utilization rate and the number of parcels.

[0057] A parcel flow management system includes, or comprises, a density-based detection system that recognizes the conveyor surface area utilization rate and the number of parcels. Sensors of the detection system are placed at selected flow entry points throughout the conveyor. The control algorithm requires recognition of individual items and the speed at which each object passes, as well as the area utilization rate of the conveyor surface to increase the conveyor area and control density. Average parcel size may also be taken into consideration. The detection package management system can also identify, locate, or track packages, parcels, or other items on the conveyor at selected locations on the conveyor by their measurements.

[0058] The present invention provides a density-based detection system conveyor package management system comprising, or essentially comprising, a programmable logic control unit or computer, sensors for detecting parcels or packages, and a collector "receiver" conveyor including separate sections of conveyors driven individually by individual motors having individual speed control units. One selected section of the collection conveyor has means such as a low-friction conveying surface, such as inclined rollers, or a high-friction conveying surface that can guide packages to a selected side of the collection conveyor. Multiple supply conveyors include separate sections of conveyors driven individually by individual motors having individual speed control units. Distance detection sensors measure the area, volume, or density of articles on the conveying surface up to the merge area of ​​each supply conveyor with the collection conveyor. The speeds of the supply and collection conveyors up to the merge area of ​​each collection conveyor are measured, and a control program in a PLC or computer can control the speeds of the collection conveyor sections and supply conveyor sections based on a calculated amount of free space on a given collection section compared to the footprint of packages on the approaching supply conveyor. A singulator conveyor may be integrated into the conveyor system and supplied by the collection conveyor.

[0059] A typical supply or collection "receiving" conveyor includes one or more separate sections of a conveyor, each individually driven by a separate motor having a separate speed control device. One selected section of the collection conveyor may have a low-friction conveying surface, such as inclined rollers, and / or a high-friction conveying surface, such as a belt, arranged in a configuration that can guide packages toward a selected side of the receiving collection conveyor. Multiple supply conveying surfaces may include separate sections of a conveyor, each individually driven by a separate motor having a separate speed control device.

[0060] A detection distance device monitors the area of ​​the collection conveyor leading up to the merge area of ​​each collection conveyor on the supply conveyor, and the detection device monitors the area of ​​the supply conveyor leading up to the merge area of ​​each collection conveyor on the supply conveyor. The bulk parcel flow management system includes a programmable logic controller or computer, and the control program in the computer or PLC can control the speed of the supply conveyor and / or collection "receiving" conveyor or sections of the collection "receiving" conveyor, and / or sections of the supply conveyor, based on the calculated amount of free space on it. A given collection section is compared to the footprint of the packages on the approaching supply conveyor. Calculated by the photo-eye and virtual encoder, pulses are generated at selected intervals to form an array, and the measured occupancy rate is determined as the occupancy rate of the parcels on the supply conveyor and / or collection "receiving" conveyor.

[0061] For example, the currently recommended requirements for a controlled conveyor with selected area and speed are 7,500 parcels per hour in 10 minutes and 8,250 parcels per hour with two (1-minute) slices (7,500 / 12,150 = 0.62 = 62% efficiency in a 10-minute test). The present invention provides a means to control the area utilization rate of the available conveying surface, achieving an efficiency of up to 75%, equivalent to 9,375 parcels per hour for the same conveyor. Furthermore, a 15% increase in area utilization rate according to the present invention results in an increase of 8,625 parcels per hour for a distance-sensing conveyor package management system conveyor.

[0062] Distance detection devices are placed at selected individual input points, connected via wired or wireless connection to a programmable logic control unit (PLC) or computer, which includes a process control algorithm for recognizing the incoming flow density in terms of both belt utilization and processing speed. These measurements can be used to make changes to reduce the parcel input flow rate, and if the flow is too sparse or too dense, it may be necessary to shut down the supply line. Similarly, if no flow is detected, it may prompt an increase in the speed of a selected input conveyor or multiple input conveyors.

[0063] The detection device can be positioned to visually inspect the surface of the singulator and is similarly used to evaluate buffer capacity utilization, primarily based on recognition of area coverage. This feedback is used to dynamically adapt the behavior of the supply line. Using a distance-detecting photoeye array may offer further advantages in terms of visibility and recordability in the system control room. Variations in parameters used for system tuning can be evaluated in a more efficient manner. Jams and other system problems are better recognized.

[0064] Multiple distance-sensing photo-eye detectors communicating with a computer-based conveyor package management system include the number and size of packages present in a given area of ​​one or more supply or collection conveyors within the package handling system. This data is collected and analyzed to measure the available area or space on the conveyor and the density of packages on it, maximizing the desired density of packages on the selected conveyor. The number of supply conveyors providing packages and their respective speeds are controlled as a function of the occupancy rate on the collection conveyor or immediately before the singulator. The computer supplies conveyor surface package density information to the conveyor speed control device, introducing packages from one or more supply conveyors to the collection conveyor. On the collection conveyor, packages are detected across the area, volume, or density of the conveyor surface, and the speed of the selected conveyor is controlled to position packages at optimal intervals, fill the conveyor area in the most efficient way, maximize the density of packages on the conveyor and the system's processing capacity, and, accordingly, minimize the number of conveyors required for the system. When the computer determines that there is sufficient space on one of the conveyor belts, for example, the collection belt, it instructs the control unit to add packages or increase the conveyor speed, causing the supply belt to add packages to the space or empty area on the collection belt.

[0065] An algorithm is used to calculate the "measured occupancy," where the sensing distance represents the percentage of belt coverage. Once the conveyor's "measured occupancy" is calculated, it is compared to the "desired occupancy" of the conveying surface area to determine the speed ratio of the downstream conveyor. The "speed ratio" is the desired occupancy divided by the measured occupancy, and the speed commanded to the conveyor is determined by the following formula. Note that (FPM) is measured in feet per minute (current conveyor speed (FPM) = downstream speed (FPM) * speed ratio ** power factor).

[0066] The distance-sensing conveyor package management system of the present invention, for measuring and controlling the density of parcels on a conveyor, uses different sensing and detection methods to determine the parcel flow density on a selected section of a supply conveyor and / or receiving conveyor as a one-dimensional linear, two-dimensional area, or three-dimensional volume, and increases the density or volume of parcels in the selected area of ​​the supply conveyor or receiving conveyor by adjusting the conveyor speed ratio, which is proportional to the ratio of the desired density to the current density.

[0067] The 2D discrete measurement method uses SICK's WTT190L photoeyes to create a sensing range table. Each photoeye has two outputs, each independently adjustable, allowing for two different ranges. The photoeyes are installed on both sides of a conveyor section at a selected distance of approximately 5 feet from the conveyor exit end, as shown in Figure 1. Optionally, multiple photoeyes can be installed in a bank or array.

[0068] As shown in Figure 1, the first side 361 of a 61-inch wide conveyor includes a photo eye 351 that measures a range of up to 13 inches along the entire conveyor, while the opposite photo eye 362 on the second side 362 of the conveyor measures a distance of up to 48 inches. A photo eye 353 on the first side of the conveyor measures a range of up to 25 inches along the entire conveyor, and the opposite photo eye 364 on the second side of the conveyor measures a distance of up to 36 inches. A photo eye 355 on the first side of the conveyor measures a range of up to 37 inches along the entire conveyor, and the opposite photo eye 366 on the second side of the conveyor measures a distance of up to 24 inches. A photo eye 357 on the first side of the conveyor measures a range of up to 49 inches along the entire conveyor, and the opposite photo eye 358 on the second side of the conveyor measures a distance of up to 12 inches.

[0069] The virtual encoder is programmed to generate pulses at selected intervals in the conveyor section, for example, at 2-inch intervals in the belt's movement. An array is created representing 120 inches, including the last 5 feet of the supply conveyor section plus another 5 feet in the receiving / collecting conveyor or downstream conveyor section. Each element of the array represents a 2-inch interval, or one pulse of the virtual encoder, and there are a total of 60 array elements in the conveyor transition section.

[0070] Depending on the combination of blocked photo-eye outputs when an encoder pulse is generated, a "measured occupancy" value is input to the current array element. The "measured occupancy" is a percentage of occupancy, where 0 represents the belt being empty or no photo-eyes are blocked, and 100 represents all photo-eyes being blocked. The photo-eyes are re-evaluated with each encoder pulse, and the result is input to the current array position. The overall measured occupancy for a 10-foot section of the conveyor (5 feet from the current belt exit and 5 feet from the downstream belt inlet) is calculated by summing all values ​​in the array and dividing by the total number of array elements.

[0071] The following table shows how to combine blocked photoeyes to input an appropriate measurement occupancy rate into the array.

[0072] [Table 1]

[0073] As shown in Table 1, the state of the first left photoeye is resolved first. Next, the state of the second right photoeye is resolved, and the percentage of charge in the encoder pulse is obtained, as shown in the chart values. Once a suitable combination is found, the algorithm terminates and the resulting value is placed in the current array element. The algorithm stores the most recent 60 values, adds them all up, and then divides by the total number of array elements to obtain the average measured occupancy, expressed as a percentage from 0 to 100. Note that "n / a" in the table above means that the condition cannot exist when the photoeye range is adjusted as shown in the figure.

[0074] Once the measured belt occupancy rate is calculated, it is compared to the belt's "desired occupancy rate" to determine the speed ratio of the downstream belt. The "desired occupancy rate" is a configurable parameter. It is expected to be in the range of 30% to 40%, but the final value should be determined on-site. The speed ratio is the desired occupancy rate divided by the measured occupancy rate. That is, if the desired occupancy rate is 30% and the measured occupancy rate is 70%, the speed ratio is 30 / 70, which is 0.429. The speed commanded to the belt is determined by the following formula. Current belt speed (FPM) = Downstream speed (FPM) * Speed ​​ratio ** Power factor

[0075] (Using IO-Link-based analog distance sensing range) The following density measurement method example uses the BALLUFF BOD0020 photoeye, which outputs the actual analog distance. By using an analog output sensor, the true distance from the end of the belt to the sensed parcel can be determined. To cancel out the effect of parcels shifted to one side, distance-sensing photoeyes are required on both sides of the belt. The sensing distance is set to the maximum value of the conveyor width, with LPE1 set to 364 and RPE1 set to 363, as shown in Figure 2.

[0076] The virtual encoder is programmed so that the conveyor section generates pulses at 2-inch intervals along the belt's movement. An array is created to represent the last 5 feet of the conveyor section plus an additional 5 feet for the downstream conveyor section, totaling 120 inches. Since each element of the array represents 2 inches, or 1 pulse of the virtual encoder, the total number of array elements during conveyor transitions is 60.

[0077] An algorithm is calculated to determine the "measured occupancy rate," which is then compared to the "desired occupancy rate" of the belt, calculated to determine the speed ratio of the downstream belt. The sensing distance represents the percentage of coverage of the belt or "conveyor surface area." Parcels detected at 60 inches will have a percentage close to 0%, while sections detected at 1 or 2 inches will have a percentage close to 100%. To obtain the "measured occupancy rate," the combination of distances sensed by both photoeyes must be used to generate the exact occupancy rate across the belt. This value is calculated for each virtual encoder pulse and placed in the array of the overall measured occupancy rate. The photoeye is re-evaluated for each encoder pulse, and the result is input to the current array position. The overall measured occupancy rate for a 10-foot section of the conveyor (5 feet at the current belt exit and 5 feet at the downstream belt inlet) is obtained by summing all values ​​in the array and dividing by the total number of array elements.

[0078] Once the measured belt occupancy rate is calculated, it is compared to the belt's "desired occupancy rate" to determine the downstream belt speed ratio. The "desired occupancy rate" is a configurable parameter. While it is expected to range from 30% to 40%, the final value should be determined on-site. The speed ratio is calculated by dividing the desired occupancy rate by the measured occupancy rate. For example, if the desired occupancy rate is 30% and the measured occupancy rate is 70%, the speed ratio is 30 / 70, or 0.429. The commanded belt speed is determined by the following formula: (Current belt speed (FPM) = Downstream speed (FPM) * Speed ​​ratio ** Power factor)

[0079] As mentioned earlier, the power factor can be used as a configurable parameter in the above formula, allowing you to set how aggressive the current belt speed becomes in response to larger corrections. A larger power factor means a more aggressive correction. In the two-dimensional domain "2D", the power factor can be set to 1.

[0080] For example, a sensing method is determined to determine the flow density in a linear region "1D", a two-dimensional region "2D", or a defined volume density "3D", and the ratio of the conveyor speed is adjusted in proportion to the ratio of the desired density to the current density.

[0081] Since the analog signal obtained from the photoeye is IO-Link, the main PLC acquires distance information from the photoeye via Ethernet. An IO-Link-based 2D architecture is shown in Figure 3. The IO-Link365 device includes a left distance-sensing photoeye 366, a right distance-sensing photoeye 367, an optional smart light stack 368, an optional vibration sensor 369, and an optional thermal sensor 370. Other sensors known in the art are expected to be linked in a similar manner.

[0082] The IO-Link master has the following features useful for 2D applications: The IO-Link master is a field-mount device. Sensors connect directly to the unit via a standard 5-pin Euro-style code set. It connects to the PLC via Ethernet. It provides the ability to connect other IO-Link input devices, such as temperature or vibration sensors. It also provides the ability to connect IO-Link output devices, such as the smart lights mentioned above. Smart lights can be configured with multiple colors, multiple flashing or static configurations, etc. Sensors have diagnostic capabilities via IO-Link to the PLC and can notify the HMI (and smart lights) if the photo eye is getting dirty. Configuration parameters for setting the device (such as range or output units) are stored in the PLC, so no configuration is required when replacing devices.

[0083] As shown in Figure 4, the distance sensor measures the flow density of parcels approaching the transition between the supply and receiving conveyors as a form of numerical integration. The distance sensor is mounted on each side of the upstream receiving conveyor ahead of the conveyor transition 732. Distance values ​​are recorded at a selected belt interval of belt movement based on encoder input with a defined resolution (e.g., 2 inches). The values ​​are recorded in an array and used to determine area utilization over a defined length of the supply conveyor. A virtual or physical encoder can be used to generate pulses that trigger the capture of distance values. The size of the array can be selected depending on the size and responsiveness of the bulk handling conveyor. For example, if the acceleration / deceleration rate is limited to 0.05G, a typical range is between 5 and 10 feet.

[0084] The conveyor section shown in Figure 4 includes an assortment of parcels of different shapes and sizes passing through multiple encoder pulse positions 730. The right photoeye (PER) is located opposite the left photoeye (PEL), and the conveyor has a width of 60 inches, with a 120-inch long segment divided into 2-inch interval measurements as shown in tabular form in the array. More specifically, the conveyor 710, having a width of approximately 60 inches "W", includes a 120-inch long measurement zone "L", which is divided into 2-inch measurements or segments 712, each representing an encoder pulse position. The right photoeye (PER) 723 and the opposite left photoeye (PEL) 725 are attached to the conveyor directly above the surface, completing a circuit extending between them for detecting articles placed between the opposing PEL and PER, such as infrared light or other emitting means. Multiple packages or parcels stationary on the conveyor in measurement zone L include a square box 713, a first small rectangular box 715, a second medium-sized rectangular box 717, a large rectangular box 719, a circle 720, and an internal space 721 representing measurement error (not significant). The actual occupancy is determined by the following formula:

[0085]

number

[0086] The array shows the actual values ​​determined for the area of ​​the items on the conveyor. As shown in the array, If PEL < 60 and PER < 60, the measured width = 60 - PER - PEL If PEL > 60 and PER > 60, the measured width = 0

[0087] Figure 5 shows a 2D series conveyor system. The supply conveyor 733 and receiving conveyor 734 include roller or belt conveyors that utilize independent motors to transport, align, and separate parcels. The number of parcels can be controlled by the conveyor principle of area utilization rate and a system having distance-sensing photoeyes positioned at the flow inlet points of selected conveyors to efficiently supply to the receiving conveyor. The conveyor transition section 732 indicates where the conveyors merge. The supply conveyor moves at speed V1 and the receiving conveyor moves at speed V2. The measuring area (total 120 inches) includes the main portion (length 96 inches) of the distal end section 736 of the supply conveyor, followed by the minor portion (length 24 inches) of the distal end section of the receiving conveyor 737, according to the following equations 2 and 3.

[0088]

number

[0089]

number

[0090] Here, DO%: Desired occupancy percentage (also known as conveyor area utilization rate) AO%: Actual occupancy percentage (also known as: Measurement conveyor area utilization rate)

[0091] <Dynamic control of BatMerge> The package flow density adjustment system, as shown in Figure 6, can be applied to the supply line of a butt merge to calculate the speed based on the flow density of the collection line approaching the merge area. Figure 6 shows a side transfer supply conveyor that carries items that intersect the flow through the collection conveyor at a 90-degree angle. Of course, the intersection angle is a matter of choice and can be any angle up to 90 degrees. In this configuration, the collection conveyor or receiving conveyor takes precedence. The flow from the supply conveyor is limited based on the available area of ​​the receiving conveyor or collection conveyor. A side supply conveyor is shown that supplies items to the receiving conveyor or collection conveyor. The speed of the side supply conveyor is controlled to achieve the desired conveyor area utilization rate on the receiving collection conveyor. The speeds of the supply conveyor, the receiving conveyor, or both the supply conveyor and the receiving conveyor are determined by an array of photo-eye measurements at selected belt area measurement positions, including both the supply conveyor occupancy definition zone and the receiving collection conveyor occupancy definition zone. Here, the desired occupancy zone 19 after merging increases in density in the selected region after the merging of the items.

[0092] As shown in Figure 6, the 2D supply and collection conveyor application shows a merger of a cross-collection conveyor and a side-transfer supply conveyor. Based on a cross-distance sensing photo-eye system that is based on the occupancy rate of the receiving conveyor, the conveyor speed is set to achieve a desired conveyor area utilization rate in the downstream portion of the collection conveyor.

[0093] The collection conveyor 734 travels at a speed (rate (velocity)) of V2, and the selected measurement area 753 is 120 inches (the measurement area can be adjusted based on the conveyor's capacity, occupancy, and speed).

[0094] The collection or receiving conveyor 734 is 20% occupied in the measurement area 753, which is 50% of the desired occupancy (40% occupancy is 50% of the target area utilization), prior to crossing with the supply conveyor 751. The supply conveyor 751 is proceeding at speed V1, and the selected measurement area 752 is 60 inches. The distal end portion of the supply conveyor is loaded to cover 50% of the measurement area 752. The speed V1 of the supply conveyor can be calculated using the following formulas, expressed in equations 4 and 5, where the desired occupancy (DO) and the actual occupancy (AD).

[0095]

number

[0096]

number

[0097] Here, DO%: Desired occupancy percentage (also known as conveyor area utilization rate) AO%: Actual occupancy percentage (also known as: Measurement conveyor area utilization rate)

[0098] For example, the approaching collection belt area has a 20% occupancy rate, and the target filling rate of the collection conveyor is 40%, which is half of the target area utilization rate. The load on the conveyor at the end of the shared conveyor (assuming 5 feet here) is measured to cover 50% of the area.

[0099]

number

[0100]

number

[0101] The parcel flow management system is used to manage, track, and merge bulk flows and includes, or comprises, a density-based sensing system compatible with a conveyor system having multiple sections 10, which include multiple conveyor modules or sections equipped with belts and / or conveyor rollers for transporting and separating items such as envelopes, mail, parcels, packages, bags, drums, boxes, or irregularly shaped items. As illustrated, a linear parcel singulator 8 and a circulating conveyor 14 are in flow communication with it. Multiple photoeye arrays provide a field of view of selected occupancy-defining zones, such as the transition area 70 of items from one conveyor 11 to another conveyor 13 (measurement areas 15 and 17 or transition points of item merging). Independent motors drive the conveyor modules or sections, generating zones that can access specific photoeyes via assigned IP addresses.

[0102] At least a distance-sensing photoeye array, one photoeye, a camera, a video camera, or other pixel detection and / or digital imaging device is placed at each input point, and a control algorithm recognizes the incoming flow density in terms of both belt utilization and throughput. These measurements can be used to make changes to reduce the parcel input flow rate, and if the flow is too dense, it may be necessary to stop the supply line. Similarly, if it is detected that there is no flow, the input conveyor speed can be increased.

[0103] As described above, a method for detecting and measuring the density of parcels on a selected section of a conveying surface includes, or comprises, a step of creating a table of sensing ranges with multiple photoeyes, each photoeye having two outputs, each independently adjustable to obtain two different ranges. Array 20 includes multiple photoeyes, which are installed on a first side and a second side opposite to the selected section of the supply and receiving conveyors at a selected distance from the discharge end of the supply conveyor and the receiving end of the receiving conveyor. A programmable virtual encoder is used to generate pulses at selected intervals along the selected section of the conveying surface. Array 20 is formed to include multiple array elements (photoeyes). Each array element represents one pulse of the virtual encoder defining a selected length of the selected distance. The average measurement occupancy of the array is calculated by determining the combination of photoeye outputs that were blocked when the encoder pulses occurred. The combination represents the percentage of the receiving conveyor's occupancy and is processed by an algorithm using a programmable logic control unit. The virtual encoder is programmable to generate pulses at selected intervals on the supply conveyor. The elements of array 20 represent one pulse of the virtual encoder, defining a selected length of a selected distance. The programmable logic control unit has an algorithm to calculate the average measured occupancy of the array, which represents the percentage of the receiving conveyor's occupancy. The measured occupancy of the receiving conveyor is compared to the desired occupancy of the supply conveyor. The speed ratio is calculated by dividing the desired occupancy by the measured occupancy. The speed of the supply conveyor V1 (speed 1), the speed of the receiving conveyor V2 (speed 2), or the speeds of both the supply and receiving conveyors are adjusted to obtain the desired occupancy or the spacing of packages on the receiving conveyor.

[0104] Photoeyes positioned to observe the singulator surface are used in a similar manner to evaluate buffer capacity utilization, primarily based on region coverage recognition. This feedback is used to dynamically adapt the behavior of the infeed lines. Using a distance-sensing photoeye array also has the advantage of improving system control room visibility. Variations in parameters used for system tuning can be evaluated in a more efficient manner. Jams and other system problems are better recognized.

[0105] As shown in Figure 7, in a preferred embodiment, a distance-sensing photoeye array and a computer-based conveyor package management system include a distance-sensing photoeye array that monitors the number and size of packages present on infeed conveyors 11, 13, 135, and 35, recirculation collection conveyor 14, singulator conveyor 8, and / or sorting conveyors in the package processing system. The photoeye data is used to measure the available area or space or volume on the conveyors and maintain a desired density of packages on the selected conveyors. The conveyor speed is controlled as a function of the occupancy rate immediately preceding a target conveyor, such as a collection conveyor or singulator. The computer supplies information to the conveyor speed controller to introduce packages from transport 33 to one or more supply conveyors 44, 46, 47, 48, 50, and collection conveyor 12, as shown in Figure 8. Packages are detected by one or more photo-eye arrays 25, 26, 27, 28, 29, and the speed of the selected conveyor and / or the speed of the packages or articles is controlled for optimal spacing of packages that maximizes the density or volume of goods on a given conveyor area and the system throughput, and accordingly minimizes the number of conveyors required for the system. When the computer determines that there is sufficient space on one of the conveyor belts, for example, the collection belt, the computer instructs the controller to add packages to the infeed belt by adding packages to the space or empty area of ​​the collection belt.

[0106] The invention utilizes a line-scan photoeye having a single row of pixel sensors. This line is continuously supplied to a programmable controller, a programmable logic control unit (PLC), or a computer, which combine the lines to create an image. Multiple rows of sensors can be used to create color images, and sensitivity can be increased by TDI (Time Delay and Integration). Traditionally, maintaining consistent light across a wide two-dimensional area has been extremely difficult, and a wide field of view is often required in industrial applications. Using a line-scan photoeye provides uniform illumination across the entire "line" that the photoeye is currently viewing. This makes it possible to sharply photograph objects passing through the photoeye at high speed, and it can be used as industrial equipment to analyze high-speed processes. It is also conceivable to use a 3D photoeye system utilizing one or more photoeyes or other pixel detection and / or digital imaging devices to detect package height and determine volume density.

[0107] A photo-eye-based density measurement system recognizes and maximizes the belt area utilization rate of a supply conveyor. Arrays containing multiple photo-eyes can be placed at selected locations on the supply conveyor and at the receiving end of the receiving conveyor. A computer with a control algorithm recognizes the area of ​​individual items, item footprints, the pass-through rate of individual objects, and the area utilization rate of the supply conveyor. Distance-sensing photo-eyes and a computer-based conveyor package management system monitor and control the speed of the supply conveyor based on the number and size of packages present on the supply conveyor. Information from receiving and collection conveyors, or singulator conveyors and / or sorting conveyors of the package processing system, can also be utilized. Photo-eye data is used to measure available area or space or volume on the conveyor and maintain a desired density of packages on the selected conveyor. The conveyor speed is controlled as a function of the occupancy rate on the collection conveyor or the occupancy rate immediately preceding the slide sorting conveyor, singulator, or receiving conveyor.

[0108] The distance-sensing parcel flow control system includes, or comprises, a section 10 of the conveyor system. Multiple photoeyes 20 detect parcels on a primary or main conveyor or collection conveyor that incorporates at least one supply conveyor 11 and one receiving conveyor 13, which are used in conjunction with a singulator 8, a hold-and-release conveyor, an accumulator, and / or strip conveyor, located downstream of the supply conveyor 11, which is typically shown linearly aligned with the singulator 8. The conveyors utilize rollers and / or belts, and each unit is powered by at least one independent motor to transport, align, and separate parcels at a selected activation rate or speed based on a desired occupancy rate of one or more selected conveyors. Thus, the degree of occupancy can be controlled in each conveyor independently of adjacent conveyors upstream or downstream, and multiple conveyors in the transport system can be started, stopped, or speed increased or decreased to increase the occupancy area of ​​a particular conveyor. The conveyor system section utilizes independent, motor-driven conveyor zones.

[0109] The conveyor system section 10 includes at least one supply conveyor 11 and a downstream receiving conveyor 13. The speed of the selected inline supply conveyor is set to achieve a desired conveyor area utilization rate on the selected downstream receiving conveyor 13. Using the photo eye 20, a view of the established supply conveyor occupancy zone 15 is presented for a given speed V2 of the parcels supplied to the receiving conveyor occupancy-defining zone 17, as the parcels are transported toward a concentrated desired occupancy zone 19 at a selected position after a transition, zone, or point 70 where the supply conveyor 11 and the receiving conveyor 13 merge.

[0110] The distance-sensing photoeye array parcel flow management system is applied from the point where goods are unloaded from the trailer to the guided conveyor, through the separation and sorting process, to the bulk supply system. As shown in Figure 8, goods unloaded from truck 33 are unloaded from one of several unloading guided conveyors 44, 46, 47, 48, 50, thereby adjusting the speed ratio of conveyors 44, 46, 47, 48, 50 and collection conveyor 12 by photoeyes 26, 27, 28, 29 which provide a field of view of the photoeyes at the merge points or respective transition points 73, 74, 75, 76, 77 of the guided supply conveyors 44, 46, 47, 48, 50 and collection conveyor 12. The collection belt 12 leads to flows from other sources, such as the unloading guided conveyor or the recirculation conveyor 14 from the sorting area, due to the output lane being full (denoted). The guided feed conveyors 44, 46, 47, 48, and 50 are adjusted as a function of the speed of the collection conveyor 12 and the occupancy rate of articles on the collection conveyor 12. The accumulating conveyor or accumulator 35 is located upstream of the singulator 8 and downstream of the collection conveyor 12 and is used as a receiving conveyor. The movement of the feed conveyors and / or collection conveyors can be adjusted as a function of the accumulator conveyor 35 immediately preceding the singulator, providing a smooth feed to the singulator 8 based on the area of ​​the conveyor occupied by packages. The downstream singulator 8 includes a singulator photoeye array 32 that provides a field of view 319 of articles on the singulator 8 and a photoeye array 41 that provides a field of view 329 of articles supplied from the adjacent accumulator conveyor 35 and merged at the transition point 78 with the singulator 8.

[0111] A computer or microprocessor-controlled system 500 that controls a bulk parcel flow management system based on a distance-sensing photoeye array adjusts several individual inputs based on the singulator's filling rate. The conveyor speeds of the supply conveyor 11, induction conveyors 44, 46, 47, 48, 50, collection conveyor 12, recirculation conveyor 14, singulator 8, and accumulator 35 can be controlled and adjusted as a function of the singulator's filling rate and input percentage occupancy.

[0112] The distance-sensing photoeye array includes at least one pair of opposing smart photoeye modules 20 capable of processing distance-sensing data, determining the optimal conveyor speed by determining the distance across the conveyor within a defined zone, which can be adjusted for each photoeye, by zooming in or out, or by selecting a specific array or region on a smart device. The smart photoeye modules process the distance-sensing data and determine the occupancy percentage within the defined zone. The IP address of each photoeye is assigned to each photoeye array 20. For example, photoeyes can be programmed or configured to define their IP addresses with a simple "right-click". The Ethernet system provides a means of sending signals to a computer via a command PC, PLDC, or VLC control system to calculate occupancy information and the desired conveyor speed. The interface is implemented via smartphones, tablets, laptops, smartwatches, standalone terminals, and / or networks. Configuration software provides a convenient interface for configuring control zones and entering control parameters. The IP address of each individual photoeye is assigned to each photoeye within the distance-sensing photoeye array system.

[0113] The bulk parcel flow management system includes a setting window for defining the "oversight" parameter and means for defining zones for which the occupancy rate is measured at any given distance-sensing photoeye array occupancy definition zone.

[0114] The control algorithm requests identification of individual items and the pass rate of individual objects, as well as the area utilization rate of the collection belt. The average size and shape of the items may also be taken into consideration. The PhotoEye array and computer-based conveyor package management system monitor the number and size of packages present on the infeed conveyor, collection conveyor, singulator conveyor, and sorting conveyor of the package handling system. PhotoEye data is used to measure the available area or space on the conveyor and maintain the desired density of packages on the selected conveyor. From the receipt of items from unloading trucks or unloading docks to the point of entry into the distribution vehicle, it is even possible to track and / or trace individual items by their labels, codes, or physical characteristics.

[0115] As shown in Figure 9, cargo is loaded and unloaded from a cargo carrier onto selected guided supply conveyors 44, 46, 47, 48, and 50 that communicate with the collection conveyor 12, which is composed of modular units in sections 120 to 134. For example, guided supply conveyor 50 crosses collection conveyor section 121 to supply goods to collection conveyor section 121, guided supply conveyor 48 crosses collection conveyor section 124 to supply goods to collection conveyor section 124, guided supply conveyor 47 crosses collection conveyor section 127 to supply goods to collection conveyor section 127, supply conveyor 46 crosses conveyor section 129 to supply goods to conveyor section 129, and supply conveyor 44 crosses collection conveyor section 132 to supply goods to collection conveyor section 132.

[0116] The recycling or recirculation conveyor 14 intersects with the conveyor section 134 and supplies to the conveyor section 134. The photo-eye array 20 can be installed at any intersection of the conveyor to control the density of the downstream conveyor.

[0117] As shown in Figure 10, the collection conveyor 12 starts from the first supply conveyor 50 and extends to the accumulator 35 and / or singulator 8, intersecting a selected number of induction supply conveyors 44, 46, 47, 48, and 50. The recycling conveyor 14 also supplies goods onto the accumulator 35 or other conveyors that intersect the collection conveyor 12 before the singulator conveyor 8. The induction supply conveyors consist of a selected number of modules or sections. For example, sections 502, 504, 506, 508, 510, and 512 are sections of the induction supply conveyor that include at least one transition point. The selected induction supply conveyor speed is set to achieve a desired conveyor area utilization rate on the selected downstream receiving conveyor 13. Photo-eye arrays 200, 210, 220, 230, 240, and 250 are used to present a field of view of the guided-feed conveyor occupancy zone 15 established for a given speed V2 of parcels supplied to the receiving conveyor occupancy-defining zone, when parcels are transported toward a concentrated desired occupancy zone at a selected position after the transition zone where the guided-feed conveyor and the receiving-collection conveyor 12 merge. The feed conveyors 44, 46, 47, 48, and 50 also include modules or conveyor sections having designated motors that operate independently to decrease or increase the density of items on the collection conveyor 12.

[0118] Each conveyor or section of a conveyor is driven by a separate variable-speed motor. This allows the speed of individual sections of the conveyor 50 to be increased or decreased, and the packages can be spaced or concentrated in a given area in a desired manner, depending on the optimal flow rate for processing by the accumulator 35 or singulator 8. For example, if a large gap is detected between two particular packages, the speed ratio of the conveyor sections between the packages is increased to fill the gap between the packages.

[0119] A distance-sensing photoeye array determines the density of parcels on the supply conveyor just before they merge with the collection belt 12 in their respective photoeye array regions 200-250. Another photoeye array 32 monitors region 319, which includes the singulator conveyor 8. Photoeyes 260, 270, 280, 290, 300, and 320 monitor selected sections of conveyor 12 just before the region where the infeed conveyor merges with the collection conveyor 12. An electrical cabinet 51 contains a video computer 500 that receives video input data from photoeye arrays 200-250 and 32. An electrical cabinet 52 contains speed controllers for the motors of all conveyors 44-50. The computer can count individual packages and calculate the package size "area" based on information from the various photoeyes monitoring the conveyors.

[0120] The singular conveyor 8 accepts randomly dispersed packages and aligns them in a line relative to the movement of the conveyor. Examples of singular conveyors are described in U.S. Patent No. 5,701,989 and U.S. Patent No. 1,0773,897, which are incorporated herein by reference in their entirety.

[0121] The singulator conveyor 8 receives packages and articles such as bags, envelopes, parcels, boxes, luggage, mail, or other items from the upstream conveyor 12. After the singulator conveyor 8, individual packages are sorted and sent to the recirculation conveyor 14. The recirculation conveyor 14 returns the packages removed in the alignment process to the selected receiving conveyor collection conveyor 12, where they are re-sorted at the singulator. The main objective of the present invention is to maintain a stable and complete flow of packages to the singulator conveyor 8 without clogging the collection conveyor 12 with packages accumulated due to surges or slugs of packages received from the upstream supply conveyor.

[0122] The singular conveyor system can handle packages of random sizes. Preferably, packages on the supply conveyor are in a single line. However, as packages are unloaded from the truck onto the selected supply conveyors 44, 46, 47, 48, and 50, it is not uncommon for packages to be spaced irregularly and oriented in random directions. Unloading is usually done in slugs. Large quantities of packages are unloaded at short time intervals.

[0123] For example, the photoeye array 30 detects parcels in the area to be transported to the occupied zones of conveyor sections 122 and 123. If the density of packages in the area is low in the occupied zone area 210 monitored by the photoeye array 210, the digital image data (pixels) is processed by the controller, and the computer controls the conveyor 48 to start, stop, slow down, or increase the rate at which packages are supplied onto the collection conveyor section 124.

[0124] Packages are transported downstream toward conveyor section 35 and monitored via photo-eye arrays 260, 270, 280, 290, 300, and 310. As packages pass through the transition sections between conveyors and subsequent distance-sensing photo-eye array occupancy zones, the computer program analyzes the overall loading of the conveyor section in pixels. Packages in specific occupancy zone areas are monitored by photo-eyes, and a digital image of the package footprint size is confirmed by computer 500. The computer determines the maximum area of ​​the conveyor based on the supply speed and downstream loading. The distance-sensing photo-eye array-based package management system utilizes the area of ​​the entire conveyor assembly to control the flow of packages to singulators, separators, scanners, or processing sites. The conveyor speed is controlled as a function of the occupancy rate immediately preceding the collection conveyor or singulator. The computer sends information to the conveyor speed controller to introduce packages from one or more supply conveyors to the collection conveyor. Packages are detected by one or more photo-eye arrays. The speed of the selected conveyor is controlled to position packages at optimal intervals, maximizing package density on the conveyor and system throughput, while minimizing the number of conveyors required for the system.

[0125] As the density of packages decreases in the transition zone between the supply conveyor and the collection conveyor 12, gaps are formed between the packages, resulting in an increased speed of the selected supply conveyor to maintain the desired flow rate of packages to the collection conveyor in order to maximize the throughput of the singulator.

[0126] In this control scheme, any selected conveyor is given priority. For example, the first supply conveyor at the beginning of the collection conveyor 12 may be given priority. Here, the collection conveyor 12 tends to be empty or lightly loaded. Therefore, packages on the first supply conveyor will typically have more empty space. The selected section of the collection conveyor 12 can be slowed down or stopped as needed to allow the subsequent supply conveyors to unload. Furthermore, the collection conveyor 12 may be slowed down or stopped, allowing more packages from the supply conveyors to push additional items onto the collection conveyor 12, thereby filling the area of ​​the collection conveyor.

[0127] The package flow management control system 5 maximizes the throughput of packages to the singulator conveyor and sorting system by utilizing the maximum area on the collection conveyor 12 or accumulator located in front of the singulator 8. Other conveyors in the conveyor system are controlled based on the maximum capacity of the singulator, determined at a constant speed, rather than the average of the surge capacity. The improved efficiency makes it possible to minimize the number of conveyors required in the system, the area, width, and / or length of the conveyors, while achieving the desired throughput at maximum efficiency.

[0128] Computer 500 uses multiple distance-sensing photoeye arrays to monitor the occupied zones of selected areas on the conveyor leading to the singulator or separation process. The computer compares the available capacity of the selected conveyor with the size of the packages on the supply conveyor. If there is sufficient space, the supply conveyor transports the packages. The programmer determines the space required for a given package. For example, the program may require that the amount of space on the collection conveyor be 1.5 times or 2 times the footprint of a given package, depending on the orientation of adjacent items. The computer also controls changes in the speed ratios of various conveyors to ensure sufficient supply to the singulator conveyor. The computer sends speed control signals to the speed controllers of all conveyor sections to adjust the package throughput.

[0129] As best illustrated in Figures 11-14, the method of inserting a package 89 from the supply conveyor 11 onto the receiving / collection conveyor 12, which includes multiple packages 81-88, by inserting the package 89 into the gap 90 between other packages on the moving collection conveyor 12, is described sequentially.

[0130] As shown in Figure 15, multiple packages 91 are transported on the collection conveyor 12. An angled supply conveyor 92 and a right-angled side supply conveyor 93 cross the collection conveyor 12 while carrying parcels 89, thereby controlling the speed of both supply conveyors 92 and 93, and inserting the parcels 89 into the gaps formed between existing parcels 91 on the collection conveyor 12.

[0131] The distance-sensing photo-eye array parcel flow control system includes multiple supply conveyors and guided supply conveyors aligned with the receiving conveyor or angled up to 90 degrees, and includes an optional recirculation conveyor 14, an optional accumulator, sorting lane, and singulator conveyor 8.

[0132] (Adjusting bulk parcel flow to the singulator to provide high sustained throughput and accuracy) The present invention applies density measuring devices and conveyor speed control to a conveyor system and can be used to adjust the flow rate of bulk 2D (two-dimensional) parcels to a singulator in a way that provides higher sustained throughput with higher novelgation accuracy. When the system is full, the collection conveyor becomes an active buffer, compressing the flow density to fill the collection line to the desired target fill level. Cavities and thin areas of the flow are pulled forward and compressed to the target fill level. Overpacked clumps or areas are thinned to reduce the possibility of jamming downstream.

[0133] Typically, the optimal bulk flow rate supplied to a singular should not be less than a 15% area utilization rate of the conveyor and not more than a 40% area utilization rate for the flow rate over a 50-foot belt length entering the singular. The actual required high, low, and average speeds should be determined based on the throughput limits within the range of average parcel size and average flow density of the conveyor system.

[0134] The flow density adjustment system determines the required speed ratio between conveyors to achieve the target flow density after transport to the downstream conveyor. When a bulk parcel flow is transferred between two end-to-end conveyors traveling at different speeds, the parcel flow density (conveyor area utilization or occupancy) before and after the transfer is proportional to the speed ratio between the conveyors, as shown in Figures 16a and 16b. As shown in Figure 16a, conveyor V1 has a 40% area utilization before the transfer, and conveyor V2 has a 20% area utilization after the transfer, (V1 = 0.5 × V2). As shown in Figure 16b, conveyor V1 has a 20% area utilization before the transfer, and conveyor V2 has a 40% area utilization after the transfer, (V1 = 2 × V2).

[0135] The flow density adjustment system can be applied to any number of series transitions that vary as a function of infeed flow rate and system-level flow priority fluctuations. For example, the package flow density adjustment system can be applied to areas where congestion and jamming are expected, such as 90-degree butt merges in applications including unloading dock collectors and primary sorting collectors, or on collection lines leading to singulators as shown earlier in Figure 5.

[0136] In addition to supplying to the singulator, the package flow density adjustment system is particularly useful for thinning the flow before the conveyor's butt merge. This allows for the inclusion of lower targets so that the collector has enough space for the merge flow to avoid jams. Following the merge region, adjustments are made to increase the target density of the receiving conveyor. Thus, as shown in Figure 17, the parcel flow is thinned before the merge region and compressed / adjusted after the merge region to return the flow to the target.

[0137] (Binary start / stop control for a butt merge conveyor) As shown in Figure 18, the application of the supply and collection conveyors illustrates the merging of the side-transition supply conveyor with the intersecting collection "receiving" conveyor. Based on a distance-sensing photo-eye system at the intersection, which is based on the occupancy rate of the receiving conveyor, the conveyor speed ratios are set to achieve the desired conveyor area utilization rate in the downstream portion of the collection conveyor. A package flow density adjustment bulk flow array can be used to manage, track, and merge bulk flow even when the conveyors do not have variable speed drives, by prioritizing the flow on the collection or receiving conveyor. If there is not enough space on the collection or receiving conveyor to receive the approaching flow near the end of the supply conveyor, the supply line can be stopped to prevent jamming.

[0138] The collection conveyor 734 travels at a ratio (speed) of V2 and has a 120-inch selective measuring area 753 (the measuring area can be adjusted based on the conveyor capacity, occupancy rate, and speed). The collection or receiving conveyor 734 is 20% occupied in the measuring area 753, which is 50% of the desired occupancy rate (40% occupancy is equal to 50% of the target area utilization rate), before crossing the supply conveyor 751. The supply conveyor 751 travels at a ratio (speed) V1 and has a 60-inch selective measuring area 752. The distal end portion of the supply conveyor is loaded to cover 50% of the measuring area 752. The speed or velocity V1 of the supply conveyor can be calculated by a formula that expresses the desired occupancy rate (DO) and the actual occupancy rate (AD) as follows:

[0139]

number

[0140]

number

[0141] Here, DO%: Desired occupancy percentage (also known as conveyor area utilization rate) AO%: Actual occupancy percentage (also known as: Measurement conveyor area utilization rate)

[0142] As shown in Figure 19, a package flow density adjustment bulk flow array can be used to manage, track, and merge bulk flow, and can be used to combine and track bulk flow transferred from different conveyors operating at different speeds. Utilization data from individual bulk flow arrays can be used to determine appropriate conveyor speed ratios.

[0143] The collection and receiving conveyor 734 travels at a ratio (speed) of V2 and has a selective measurement area 737 (the measurement area can be adjusted based on the conveyor's capacity, occupancy rate, and speed). The collection or receiving conveyor 734 occupies a measurement area 737 with a desired occupancy rate selected based on the target area utilization rate, before intersecting with the supply conveyor 751. The supply conveyor 753 travels at a ratio (speed) V1 and has a selective measurement area 736. The distal end portion of the supply conveyor is loaded to cover a selected percentage of the measurement area 736. The speed V1 of the supply conveyor can be calculated by a formula that expresses the desired occupancy rate (DO) and the actual occupancy rate (AD) as follows:

[0144]

number

[0145]

number

[0146] Here, DO%: Desired occupancy percentage (also known as conveyor area utilization rate) AO%: Actual occupancy percentage (also known as: Measurement conveyor area utilization rate)

[0147] Each pulse of the measured width value of the virtual encoder in the array measurement area 736 is measured from the last register and added to the value of the first register of the photodetector. The value accumulated in the first register of the photodetector for each virtual encoder is shifted to the second register, the first register is set to zero, and the area utilization rate is obtained as the sum of the array values. The third collection and supply conveyor 739 runs parallel to and in the opposite direction to the receiving conveyor 734 at a ratio V3, includes a selection measurement area 738 (the measurement area can be adjusted based on conveyor capacity, occupancy, and speed), and intersects with the supply conveyor 751. The combined bulk flow array can be used to track bulk flow migration from different conveyors having different speeds.

[0148] Figure 20 shows an example of dynamic merging with an integrated stop-start conveyor to calculate the speed ratio with multiple variable-speed conveyors. For example, PDF-3 stops when the occupancy rate of the receiving array exceeds 60% at the bottom of the chute and restarts when it falls below 45%. The width value of each virtual pulse of PD7-3 is virtually added to the first register at the bottom of the chute. The actual occupancy used to trigger the start-stop of PDF-3 should use only a portion of the PDF-4 array. With each recirculation virtual pulse, the value of the last register moves to the position where the opening of the PC7-4 array begins. The recirculation rate is calculated using a dynamic butt-merge formula-based collection bulk array that includes the sum of values ​​contributed from both recirculation and supply in the recirculation entry zone.

[0149] Thus, the distance-sensing photoeye array apparatus is a device for measuring and controlling the density of articles on a conveyor, comprising or composed of a supply conveyor, a butt-merge conveyor, and a receiving conveyor, each having an independent drive motor. The supply conveyor includes a measuring distance-sensing field at its distal discharge end adjacent to the receiving conveyor. The receiving conveyor includes a measuring distance-sensing field at its distal receiving end adjacent to the supply conveyor. The butt-merge conveyor includes a measuring distance-sensing field at its distal discharge end adjacent to the receiving conveyor, after the measuring distance-sensing field of the supply conveyor and before the measuring distance-sensing field of the receiving conveyor. At least one distance-sensing photoeye array includes a virtual encoder and signal-generating and detection means extending across the surfaces of the measuring fields of the supply conveyor, the butt-merge conveyor, and the receiving conveyor. A computer calculates a desired occupancy percentage of the receiving conveyor and the actual occupancy percentage of the receiving conveyor. The programmable logic control unit controls the conveyor speed of the supply conveyor, butt merge conveyor, and receiving conveyor, and controls the stop-start operation of the supply conveyor and / or butt merge conveyor based on signals received from a distance sensing detection device that identifies gaps between items on the receiving conveyor that are sufficient space to insert additional packages from the supply conveyor, and the density of items on the supply conveyor and butt merge conveyor.

[0150] The detailed explanation above is primarily for the purpose of clarifying understanding, and no unnecessary limitations should be understood from it. Modifications will be obvious to those skilled in the art upon reading this disclosure and can be made without departing from the spirit of the invention and the scope of the appended claims. Accordingly, the invention is not intended to be limited by the specific examples presented herein. Rather, it is intended to cover the spirit and scope of the appended claims.

Claims

1. Package flow density adjustment, A step of utilizing a series of sensors to collect multiple measurements of a package moving along a supply conveyor and a collection conveyor having variable speed motors, The steps include storing and analyzing the multiple measurements in software to determine the area utilization rate over a defined length of the conveyor, A step of variablely controlling the speed of the supply conveyor and the collection conveyor using a programmable logic control device to achieve a desired percentage area utilization rate or desired occupancy percentage of the packages on the supply conveyor and the collection conveyor, including, method.

2. The series of sensors is at least a single vision sensor located on the top of the conveyor, or at least two vision sensors located on both sides of the conveyor. The method according to claim 1.

3. The aforementioned series of sensors are distance sensors such as ultrasonic sensors, infrared proximity sensors, light detection and distance measuring (LIDAR) sensors, or vertical cavity surface-emitting (VCSEL) sensors. The method according to claim 1.

4. The programmable logic control device stops the supply conveyor when the calculated speed of the conveyor falls below its minimum speed, and restarts the conveyor when the calculated required speed exceeds 110% of the preset minimum speed. The method according to claim 1.

5. The supply conveyor is driven by a single-speed motor networked to the programmable logic control device, and the supply conveyor is started and stopped at appropriate intervals to ensure that the desired percentage area utilization rate is achieved when merging with the collection conveyor. The method according to claim 1.

6. The supply conveyor stops when the calculated speed falls below its minimum speed, and restarts when the calculated required speed exceeds 110% of the conveyor's preset minimum speed. The method according to claim 5.

7. A method for optimizing the flow density of packages on a collection conveyor by variably adjusting the speed of a supply conveyor, The adjusted speed of the feed conveyor is calculated by multiplying the ratio of the desired occupancy percentage of the feed conveyor to the actual occupancy percentage of the feed conveyor by the speed of the collection conveyor. method.

8. The actual occupancy percentage of the feed conveyor is determined by a numerical value of a pair of distances measured at regular intervals by a series of opposing distance sensors as the package moves along the supply conveyor upstream of the junction with the collection conveyor. The method according to claim 7.

9. The aforementioned fixed interval is determined by a physical encoder input having a predetermined resolution attached to the conveyor, or by a virtual encoder input. The method according to claim 8.

10. The speed of the supply conveyor is controlled so that the percentage area utilization rate of the collection conveyor does not fall below 15% and does not exceed 40%. The method according to claim 1.

11. The aforementioned supply conveyor is 0.05 G (0.5 m / s ２ ) It can accelerate and decelerate at the following speeds: The method according to claim 1.

12. A method for adjusting the package flow rate density, The process includes the step of merging multiple first packages from a first supply conveyor and multiple second packages from a second supply conveyor into an intermediate flow control conveyor that supplies to a collection conveyor. The area utilization rate of the first supply conveyor is determined by a series of distance sensors located upstream of the junction between the first supply conveyor and the intermediate flow control conveyor. The area utilization rate of the intermediate flow control conveyor is determined by a series of distance sensors positioned upstream of the junction between the intermediate flow control conveyor and the collection conveyor. The first package from the first supply conveyor is dynamically supplied to the intermediate flow control conveyor by variably adjusting the speed of the first supply conveyor, and a first desired percentage area utilization rate of the intermediate flow control conveyor is achieved that is sufficient to merge the second package from the second supply conveyor into the intermediate flow control conveyor. The speed of the intermediate flow control conveyor is adjusted to achieve a second desired percentage area utilization rate of the collection conveyor. method.

13. The area utilization rate of the second supply conveyor is also determined by a series of distance sensors positioned upstream of the junction between the second supply conveyor and the intermediate flow control conveyor, and the first desired percentage area utilization rate of the intermediate flow control conveyor can be achieved by changing the speed of either the first supply conveyor or the second supply conveyor. The method according to claim 12.

14. The first supply conveyor is arranged linearly with the intermediate flow control conveyor, and the second supply conveyor is butt-merged perpendicularly with respect to the intermediate flow control conveyor. The method according to claim 12.

15. The first supply conveyor and the second supply conveyor are in contact perpendicularly with the intermediate flow control conveyor. The method according to claim 12.

16. At least two supply conveyors merge with the intermediate flow control conveyor. The method according to claim 12.

17. An improved conveyor parcel flow density adjustment method in which parcel flow is measured and controlled from a supply conveyor and a receiving conveyor using a programmable logic control device, A transition zone is selected between the supply conveyor and the receiving conveyor, and before adjacent butt merge conveyors, each having independent drive means. The distance sensing field for measurement is determined in the selected transition zone. The actual percentage of occupancy is determined for the supply conveyor occupancy definition zone. The actual occupancy percentage is determined for the defined zone of the receiving conveyor occupancy rate. After merging multiple parcels from the supply conveyor to the receiving conveyor, a desired percentage of occupancy is selected for the receiving conveyor. The parcels from the supply conveyor are supplied to the receiving conveyor occupancy-defining zone at a selected rate ratio, with the flow rate of the parcels being reduced in front of the merge area of ​​the receiving conveyor. The parcels are merged in the conveyor region of the transition zone between the supply conveyor and the receiving conveyor, and the conveyor speed ratio is adjusted in proportion to the ratio of the desired density to the current density to increase the density or volume of the parcels in the selected region of the receiving conveyor, and the parcels are compressed on the collection conveyor after the merging region. The improvement involves the supply conveyor and the receiving conveyor each acting as an active buffer that compresses the flow density, pulling and compressing the parcels forward to fill the collection conveyor to a desired target level, thereby avoiding flow cavities and thin areas, thinning out blobs and overfilled areas, and reducing the possibility of downstream jams. Improved conveyor parcel flow density adjustment method.

18. The step includes generating a sensing range table using multiple distance-sensing photoeye arrays, Each distance-sensing photoeye array includes two outputs, each independently adjustable to acquire two different ranges, and the multiple distance-sensing photoeye arrays are installed at selected distances from the discharge end of the supply conveyor and the receiving end of the receiving conveyor, on the first side and the second side opposite to the selected field of measurement of the supply conveyor and the receiving conveyor, and pulses are generated at selected intervals along the field of measurement of the conveying surface using a programmable virtual encoder. The parcel flow rate density adjustment method according to claim 17.

19. The step of generating an array that includes multiple distance-sensing photoeye arrays, Each of the plurality of distance-sensing photoeye arrays represents a single pulse of a virtual encoder that defines a selected length of a selected distance, and the average measurement occupancy of the array is calculated by determining a combination of outputs of the blocked distance-sensing photoeye arrays when an encoder pulse representing a percentage of the filling amount of the receiving conveyor is generated using a programmable logic control device that uses an algorithm. The measured occupancy rate of the supply conveyor and the butt merge conveyor is compared with a desired occupancy rate of the receiving conveyor, the supply conveyor and / or the butt merge conveyor are started and stopped, or the speed ratio is calculated by dividing the desired occupancy rate by the measured occupancy rate, and the speed of the supply conveyor, the butt merge conveyor, or the receiving conveyor, or the supply conveyor, the butt merge conveyor, and the receiving conveyor is adjusted to obtain a desired occupancy rate on the receiving conveyor. The parcel flow rate density adjustment method according to claim 17.

20. A parcel flow rate density adjustment method for measuring and controlling the density of parcels on a conveyor, Each of the supply conveyor, receiving conveyor, and butt merge conveyor has an independent drive motor, The supply conveyor includes a distance sensing field for measurement at the distal discharge end adjacent to the receiving conveyor, The receiving conveyor includes a distance sensing field for measurement at the distal receiving end adjacent to the supply conveyor, The butt merge conveyor includes a distance sensing field for measuring the distal receiving end of the receiving conveyor, The distance-sensing photoeye array has a virtual encoder and signal generation and detection means, and extends across the measurement field of the supply conveyor, the butt merge conveyor, and the receiving conveyor. The computer calculates the desired percentage of the receiving conveyor's occupancy and the actual percentage of the receiving conveyor's occupancy. The programmable logic control unit controls the conveyor speed and movement based on signals received from the photoeye array, which identify gaps between packages in the receiving conveyor that are sufficient space for the insertion of additional packages from the supply conveyor or the butt merge conveyor. The receiving conveyor acts as an active buffer, pulling and compressing the parcels forward to fill the collection conveyor to the desired target level, avoiding voids and thin areas in the flow, thinning out clumps and overfilled areas, and reducing the possibility of downstream jams. Parcel flow rate density adjustment method.

21. Density includes area, volume, weight, or a combination thereof. The parcel flow rate density adjustment method according to claim 20.

22. Multiple distance-sensing photoeye arrays are positioned at separate input points selected to communicate via wired or wireless connection to a programmable logic control unit, a "PLC," or a computer, and include a process control algorithm that identifies inflow density in terms of both belt utilization and throughput ratio. The parcel flow rate density adjustment method according to claim 20.

23. The distance-sensing photoeye array defines a density-based detection system that identifies belt area utilization and parcel count. The parcel flow rate density adjustment method according to claim 20.

24. The control algorithm identifies individual items, the speed at which the individual items pass, and the area utilization rate of the collection belt. The parcel flow rate density adjustment method according to claim 20.

25. The control algorithm identifies the average parcel size based on area, volume, parcel length, parcel width, parcel weight, and parcel height. The parcel flow rate density adjustment method according to claim 20.

26. The control algorithm includes identifying, locating, or tracking packages, parcels, or other items on the supply conveyor by digital image, scanner code, or digital footprint. The parcel flow rate density adjustment method described in claim 20.

27. The distance sensing device is positioned at a separate input point selected to communicate via wired or wireless connection to a programmable logic control unit, a "PLC," or a computer, which includes a process control algorithm that identifies the inflow density in terms of both belt utilization rate and throughput ratio. The parcel flow rate density adjustment method according to claim 20.

28. The computer is interfaced with the conveyor computer control system via smart electronic devices, including smartphones, computer tablets, laptop computers, and computer-based devices for visual assistance that can communicate with computer systems, and controls and integrates with the conveyor computer control system. The parcel flow rate density adjustment method according to claim 20.

29. A parcel flow density adjustment device for measuring and controlling the density of articles on a conveyor, A supply conveyor and a receiving conveyor, each having an independent drive motor, wherein the supply conveyor includes a distance sensing field for measuring the distal discharge end adjacent to the receiving conveyor, and the receiving conveyor includes a distance sensing field for measuring the distal receiving end adjacent to the supply conveyor, A virtual encoder and signal generation and detection means, comprising at least one distance-sensing photoeye array extending across the surface of the measurement field of the supply conveyor and the measurement field of the receiving conveyor, The receiving conveyor or collection conveyor or singular conveyor or sorting conveyor or a combination thereof is positioned at the input point and comprises at least one detection device selected from the group consisting of a camera, a pixel detection device, a digital imaging device, and a combination thereof. A computer that calculates the desired percentage of the receiving conveyor's occupancy and the actual percentage of the receiving conveyor's occupancy, A programmable logic control device controls the conveyor speed and movement based on a signal received from a distance sensing device that identifies gaps between packages on the receiving conveyor that are sufficient space for the insertion of additional packages from the supply conveyor. Equipped with, The receiving conveyor acts as an active buffer, pulling and compressing the parcels forward to fill the collection conveyor to the desired target volume, avoiding voids and thin areas in the flow, thinning out clumps and overfilled areas, and reducing the possibility of downstream jams. Parcel flow density adjustment device.

30. A parcel flow density adjustment device for measuring and controlling the density of articles on a conveyor, A supply conveyor, a butt merge conveyor, and a receiving conveyor, each having an independent drive motor, wherein the supply conveyor includes a distance sensing field for measuring the distal discharge end adjacent to the receiving conveyor, the receiving conveyor includes a distance sensing field for measuring the distal receiving end adjacent to the supply conveyor, and the butt merge conveyor includes a distance sensing field for measuring the distal discharge end adjacent to the receiving conveyor, after the distance sensing field for measuring the supply conveyor and before the distance sensing field for measuring the receiving conveyor. A virtual encoder and signal generation and detection means, comprising at least one distance-sensing photoeye array extending across the surface of the measurement field of the supply conveyor, the measurement field of the butt merge conveyor, and the measurement field of the receiving conveyor, A computer that calculates the desired percentage of the receiving conveyor's occupancy and the actual percentage of the receiving conveyor's occupancy, A programmable logic control device controls the conveyor speed of the supply conveyor, the butt merge conveyor, and the receiving conveyor, and the start and stop operations of the supply conveyor and / or the butt merge conveyor, based on signals received from a distance sensing detection device that identifies gaps between packages on the receiving conveyor that are sufficient space for the insertion of additional packages from the supply conveyor. Equipped with, Parcel flow density adjustment device.

31. Furthermore, the receiving conveyor or collection conveyor or singular conveyor or sorting conveyor or a combination thereof is positioned at the input point and comprises at least one detection device selected from the group consisting of a camera, a pixel detection device, a digital imaging device, and a combination thereof. The parcel flow rate density adjustment device according to claim 30.

32. Furthermore, it includes multiple opposing distance-sensing photoeye arrays for generating a sensing range table, Each distance-sensing photoeye array includes two outputs, each independently adjustable to acquire two different ranges, and the plurality of distance-sensing photoeye arrays include a first distance-sensing photoeye array installed on the first side of the conveyor and a second distance-sensing photoeye array installed on the second side opposite the conveyor, in a transition zone including the distance-sensing field for measuring the supply conveyor and the distance-sensing field for measuring the receiving conveyor. The parcel flow rate density adjustment device according to claim 30.

33. The virtual encoder is programmable to generate pulses at selected intervals on the supply conveyor. The parcel flow rate density adjustment device according to claim 30.

34. The computer is interfaced with the conveyor computer control system via smart electronic devices, including smartphones, computer tablets, laptop computers, and computer-based devices for visual assistance that can communicate with computer systems, and controls and integrates with the conveyor computer control system. The parcel flow rate density adjustment device according to claim 30.

35. The distance-sensing photoeye array includes a plurality of array elements, each of which represents one pulse of the virtual encoder that defines a selected length of the distance-sensing field to be measured. The parcel flow rate density adjustment device according to claim 30.

Images