PACKAGING MATERIAL CONVEYANCE SYSTEM HAVING AIR DUCTS

A packaging material conveyance system is configured to convey protective packaging articles including pads made of paper dunnage from a protective packaging machine to a receptacle. A main duct receives the articles output by the protective packaging machine and transports the articles to the receptacle. The articles are conveyed by an airflow generated by a blower that propels the articles through the main duct, and are deposited into the receptacle after being released through an outlet. The outlet may be associated with a diverter that forms part of the main duct in a closed position, and is configured to release the articles into the receptacle in an open position.

BACKGROUND

(a) Technical Field

The present disclosure is directed to a packaging material conveyance system, more particularly, to the packaging material conveyance system including at least one air duct for conveying packaging articles from a protective packaging machine to a receptacle.

(b) Description of the Related Art

It is known to produce protective packaging articles including relatively lightweight plastic-based articles such as inflatable cushioning and air pillows, and move such articles from one place to another, e.g., using ducting. However, paper-based protective packaging articles have different considerations, and typically are heavier than the plastic-based articles. Such paper-based protective packaging articles, including dunnage, may be formed into paper packing cushions or pads. The paper-based articles may become jammed if conveyed using the same type of ducting as plastic-based articles.

Previous ducts used to convey paper-based articles rely on a blower producing an airflow on a single side. This type of air duct may be suitable for moving plastic-based articles, but presents problems for moving paper-based articles, which may have a relatively larger size and/or weight. With stiffer, larger dunnage, this can have the effect of forcing the dunnage against an opposite wall of the duct, resulting in the dunnage becoming stuck within the wall of the duct. It also can make it more likely that the dunnage becomes stuck at bends or joints of the duct. It would be desirable to provide a solution to allow paper-based articles to be conveyed through ducting without becoming stuck or jammed.

SUMMARY

According to one aspect of the present disclosure, a packaging material conveyance system for conveying protective packaging articles from a protective packaging machine to a receptacle may include: a main duct having a packaging article inlet configured to receive formed packaging articles, and having a first outlet configured to allow the packaging articles to exit therefrom, the main duct being elongated and configured to transport the articles in a longitudinal direction within the main duct from the packaging article inlet to the first outlet; and a blower assembly operably connected to the main duct to generate airflow that enters the main duct from at least two non-adjacent sides of the main duct to propel the articles through the main duct.

The packaging article inlet may be connected to an outlet of the protective packaging machine that converts a high-density supply material into the packaging articles having a lower density than the supply material.

The receptacle may be arranged at the first outlet, and configured to receive the articles conveyed by an internal duct airflow from the packaging article inlet to the first outlet.

The conveyance system may further include a blower duct section fluidly connecting the blower assembly and the main duct to introduce the airflow at an angle relative to the longitudinal direction of the main duct.

The blower duct section may include first and second blower duct sections, and the airflow may include first and second air streams configured to enter the main duct via the first and second blower duct sections at first and second angles, respectively. For example, the first and second angles may be the same. The first and second angles may be not greater than about 90°, more preferably, the first and second angles may be not greater than about 60°.

According to the present disclosure, the first and second air streams may be configured to energize boundary layers on top and bottom sides of the articles, respectively, so as to accelerate the articles from the packaging article inlet of the main duct. For example, the first and second air streams may be configured to engage opposite sides of the articles.

According to the present disclosure, the blower may include a first blower for generating the first air stream and a second blower for generating the second air stream. For example, the first blower and the second blower may be arranged on the at least two non-adjacent sides of the main duct. The first and second blowers may be arranged proximate the packaging article inlet of the main duct.

According to the present disclosure, the main duct may include first and second duct sections, the first and second duct sections each defining a substantially straight path. The first and second duct sections may be rectangular in shape. For example, the first duct section may be generally horizontal and defines a change in elevation. An elbow of the main duct may be arranged between the first and second duct sections, the elbow being wider than the first and second duct sections. The main duct may be configured to receive the articles at the packaging article inlet that have been cut and separated by the protective packaging machine. For example, the articles may be paper dunnage pads, such as two-ply paper pads.

According to another aspect of the present disclosure, a packaging material conveyance system for conveying protective packaging articles from a protective packaging machine to a receptacle may include: a main duct extending a predetermined length from a packaging article inlet to at least a first outlet, the main duct configured to receive the articles output by the protective packaging machine and transport the articles to a first outlet corresponding to the receptacle, the main duct defining a longitudinal direction corresponding to a direction of travel of the articles in the main duct; a first blower operably connected to a first blower duct section for generating a first airflow that enters the main duct at a first predetermined angle relative to the longitudinal direction; and a second blower operably connected to a second blower duct section for generating a second airflow that enters the main duct at a second predetermined angle relative to the longitudinal direction, wherein the first and second air streams are configured to propel the articles through the main duct.

According to a further aspect of the present disclosure, a packaging material conveyance system for conveying protective packaging articles from a protective packaging machine to a receptacle may include: a main duct extending a predetermined length from a packaging article inlet to at least a diverter, the main duct configured to receive the articles output by the protective packaging machine and transport the articles to the diverter corresponding to the receptacle, the main duct defining a longitudinal direction corresponding to a direction of travel of the articles in the main duct; the diverter being configured to act as an outlet in an open position and as part of the main duct in a closed position, wherein in the open position the packaging articles are diverted into the receptacle and when in the closed position the packaging articles are configured to continue to an additional receptacle that follows the receptacle; a blower operably connected to the main duct, the blower oriented at an angle to the longitudinal direction of the main duct so as to generate airflow to propel the articles through the main duct; and the receptacle associated configured to receive the articles conveyed by the internal duct airflow from the inlet to the diverter.

According to the present disclosure, a portion of the diverter may be configured to rest within a notch when in the open position.

DETAILED DESCRIPTION

The following discussion omits or only briefly describes conventional features of the disclosed technology that are apparent to those skilled in the art. Reference to various embodiments does not limit the scope of the claims attached hereto. Additionally, any examples set forth in this specification are intended to be non-limiting and merely set forth some of the many possible embodiments for the appended claims. Further, particular features described herein can be used in combination with other described features in each of the various possible combinations and permutations. A person of ordinary skill in the art would know how to use the instant disclosure, in combination with routine experiments, to achieve other outcomes not specifically disclosed in the examples or the embodiments.

Protective packaging articles are configured for placement within a packaging container or between items being shipped or stored, to protect the items, fill void space within the packaging container, and/or to prevent or inhibit the items from moving around within the container. The protective packaging articles include protective-fill articles that are typically provided individually or as a plurality of units that are configured to be placed into the void space to provide a desired level of packaging. Such units typically are of a predetermined size or can have predetermined dimensions and/or be selectively configurable in another dimension, such as length. In some examples, the size of the protective-fill articles can be configurable in a plurality or all of their dimensions. Protective-fill articles are typically resiliently compressible around corners, edges, and/or sides of a packaged item to fill the void space around the item, instead of assuming a solid shape that corresponds to the void space around the item. Protective-fill articles include, for example, void-fill articles and cushioning articles.

Void-fill articles typically provide minimal cushioning properties and are relatively soft. They are typically used to fill empty void space in packaging containers to reduce the movement within the container of lightweight items that are not delicate, such as a thin book. An example of void-fill includes crumpled-paper dunnage with a fairly weak loft pattern and other space fillers that are easily compressible.

Cushioning articles are configured to provide cushioning to the packaged items and protection to various degrees against shocks and impact. Examples of cushioning materials include inflatable air pillows and cushions, bubble wrap, paper dunnage with a loft structure capable of withstanding moderate shocks and impact, foam sheets, and packing peanuts. Typically, both void-fill and cushioning articles are provided as a plurality of units of one or more similar sizes, typically common predetermined sizes, although in some applications the void-fill or cushioning articles can be made to custom sizes. Some cushioning articles are also packaging containers, such as padded mailers or other containers with a padded wall.

Paper-based protective packaging, or dunnage, is produced by crumpling or otherwise deforming paper stock. More specifically, paper dunnage is produced by running a generally continuous strip of paper through a dunnage conversion machine. The continuous strip of paper can be provided from, for example, a roll of paper or a fanfold stack of paper. The dunnage conversion machine converts the paper stock material into a lower density paper dunnage material using, for example, opposing rollers between which the paper stock material is passed. The rollers grip and pull the paper stock material from the roll or stack, and deform the paper stock material as the material passes between the rollers. The resulting paper dunnage can be cut into desired lengths to form individual pieces (or paper cushions or pillows) that can be provided to effectively fill a void space within a container holding a product.

A protective packaging machine conveyance system is also referred to herein as a conveyance system. As discussed above, conveyance systems are used to transport packaging articles (e.g., pieces of paper dunnage) from a protective packaging machine to one or more receptacles. Current conveyance systems typically are designed to convey lightweight packaging articles such as inflated air cushions or similar packaging material from a source of packaging articles (e.g., an inflation and sealing device, dunnage conversion machine or similar device) to a location where the packaging articles can be used. However, current conveyance systems struggle to convey heavier packaging articles such as paper pads, mailers or similar packaging articles. The heavier packaging articles have been found to cause jams and other similar issues within the conveyance systems. The present disclosure relates to improvements in conveyance systems.

A conveyance system used in conjunction with a protective packaging machine for conveying paper dunnage utilizes air ducts to transport pieces of the paper dunnage (i.e., paper cushions or pillows) from the outlet of the protective packaging machine (e.g., a dunnage conversion machine) to individual receptacles. The receptacle may be an overhead hopper associated with a workstation, and the pieces of paper dunnage may be conveyed by one or more air blowers and ducting to the overhead hopper at the workstation.

Referring toFIGS.1and2, a conveyance system100is shown. The conveyance system100transports packaging articles created at a protective packaging machine110(e.g., a dunnage conversion machine) to one or more receptacles122such as overhead hoppers or other holding containers, vessels, or repositories. Alternatively, instead of the receptacles (e.g., overhead hoppers)122, the receptacles122can be replaced by a conveyor belt such as a snake conveyor.

Preferably each of the receptacles122is associated with one or more workstations120where the packaging articles can be retrieved by an operator for packaging and shipping purposes. For example, the packaging articles may be used to surround a fragile item in a box being shipped or a similar use. The packaging articles created by the protective packaging machine110preferably are paper cushions or pillows (i.e., paper dunnage), but the conveyance system100may be used to transport other articles including cushioning materials such as inflatable air pillows and cushions.

When the protective packaging machine110is a dunnage conversion machine, it is configured to create paper-based protective packaging dunnage from stock material such as stock paper. The stock material is converted from a first high-density configuration to a second low density configuration. The stock material may be a fanfold stack of paper125in a high-density configuration. Alternatively, the stock material can be a roll of paper with a high-density configuration. Optionally, the stock material is a recyclable or carbon neutral material.

As shown inFIG.2, the fanfold stack of paper125includes a plurality of stacks125a,125b,125c,125dand125e, where each stack may include a single or a plurality of blocks (e.g., four blocks). Typically, the last sheet of a block is spliced to a first sheet of a next block, such that the blocks are daisy-chained together. Examples of the fanfold stack of paper125include stock material with 30-inch transverse widths and/or 15-inch transverse widths. Preferably these sheets are fan-folded as single layers. Alternatively, multiple layers of sheets can be fan-folded together such that dunnage is made of superimposed sheets that are crumpled together in the conversion process. Any suitable stock material may be used. For example, the stock material can have a basis weight of about 20 lbs. to about 100 lbs. The stock material may comprise paper stock stored in a high-density configuration having a first longitudinal end and a second longitudinal end, that is later converted into a low-density configuration by the protective packaging machine110. The stock material can be a ribbon of sheet material that is stored in a fan-fold structure as shown inFIG.2.

The supply units of stock material may have fan-fold configurations. For example, a foldable material, such as paper, may be folded repeatedly to form a stack or a three-dimensional body. The term “three-dimensional body,” in contrast to the “two-dimensional” material, has three dimensions all of which are non-negligible. A continuous sheet, e.g., a sheet of paper, plastic, or foil, can be folded at multiple fold lines that extend transversely to a longitudinal direction of the continuous sheet, or transversely to the feed direction of the sheet. For example, folding a continuous sheet that has a substantially uniform width along transverse fold lines can form or define sheet sections that have approximately the same width. The continuous sheet can be folded sequentially, in opposite or alternating directions, to produce an accordion-shaped continuous sheet. For example, the folds may form or define sections along the continuous sheet, and the sections may be substantially rectangular.

For example, sequentially folding the continuous sheet may produce an accordion-shaped continuous sheet with sheet sections that have approximately the same size and/or shape as one another. Multiple adjacent sections that are defined by the fold lines can be generally rectangular, and can have the same first dimension, e.g., a dimension corresponding to the width of the continuous sheet, and the same second dimension that is generally along longitudinal direction of the continuous sheet. For example, when the adjacent sections are contacting one another, the continuous sheet may be configured as a three-dimensional body or a stack, in an accordion shape that is formed by the folds and be compressed, so that the continuous sheet forms a three-dimensional body or stack.

The fold lines of the stock material can have any suitable orientation relative to one another, as well as relative to the longitudinal and transverse directions of the continuous sheet. Also, the stock material unit can have transverse folds that are parallel one to another. For example, the sections that are formed by the fold lines can be compressed to form a three-dimensional body that is a rectangular prismoid. Also, the stock material can have one or more folds that are non-parallel relative to the transverse folds.

The stock material can be provided as any suitable number of discrete stock material units. For example, two or more stock material units can be connected together to provide a continuous feed of material into the dunnage conversion machine. The material can be fed from the connected stock material units sequentially or concurrently, i.e., in series or in parallel. The stock material units can have various suitable sizes and configurations, and may include one or more stacks or rolls of suitable sheet materials. The term “sheet material” refers to a material that is generally sheet-like and two-dimensional, i.e., two dimensions of the material are substantially greater than the third dimension so that the third dimension is negligible or de minimus in comparison to the other two dimensions. Also, the sheet material can be generally flexible and foldable, such as the illustrative materials described herein.

The stock material units can include an attachment mechanism that connects multiple units of stock material, for example, to produce a continuous material feed from multiple discrete stock material units. The respective end and beginning of consecutive rolls can be joined by adhesive or other suitable means, to facilitate daisy-chaining the rolls together to form a continuous stream of sheet material that can be fed into the protective packaging machine, e.g., a dunnage conversion machine. Examples of suitable dunnage conversion machines include those disclosed in U.S. Patent Application Publication No. US 2019/0193364 published on Jun. 27, 2019; U.S. Pat. No. 11,235,548 issued Feb. 1, 2022; and U.S. Ser. No. 18/340,805 filed on Jun. 23, 2023.

Folding a continuous sheet along the transverse fold lines can form or define generally rectangular sheet sections. The rectangular sheet sections can stack together by, for example, folding the continuous sheet in alternating directions, to form the three-dimensional body that has longitudinal, transverse, and vertical dimensions. The stock material from the stock material units can be fed through an intake to the protective packaging machine shown inFIGS.1and2. In some applications, the transverse direction of the continuous sheet of stock material can be greater than one or more dimensions of the intake. For example, the transverse dimension of the continuous sheet can be greater than the diameter of a generally round intake. Reducing the width of the continuous sheet in this manner at the start of the conversion process can facilitate passage thereof into the intake. The decreased width of the leading portion of the continuous sheet may facilitate smoother entry and/or transition of a daisy-chained continuous sheet and/or may reduce or eliminate catching or tearing of the continuous sheet. Moreover, reducing the width of the continuous sheet at the start thereof can facilitate connecting together or daisy-chaining two or more stock material units. For example, connecting or daisy-chaining material with a tapered section may be accomplished using smaller connectors or splice elements than would be required otherwise. Also, tapered sections may be easier to manually align and/or connect together in comparison to full-width sheet sections.

Referring toFIGS.1and2, the protective packaging machine110preferably converts one or multiple plies of paper-based stock material into a pad. For example, the multiple plies are held together by a zipper formed by the protective packaging machine110. The protective packaging machine110may include a separating/cutting device having a blade, and be configured to separate or cut the packaging articles prior to the packaging articles entering the main duct130. The main duct130preferably is arranged at an outlet of the protective packaging machine110downstream of the blade of the separating/cutting device. In some examples, the pad is a predetermined length and thickness. For example, the pad may have a minimum height of about 2 cm or 4 cm and a maximum height of about 6 cm or 8 cm. The pad may have a minimum length of about 1 cm or 3 cm and a maximum length of about 80 cm or 100 cm. The height and length of the pad may be set in advance, or during operation of the protective packaging machine110to any range within the above minimums and maximums.

Alternatively, the protective packaging machine110may be replaced by an accumulator or dispenser of premade protective packaging articles, e.g., dunnage. As a further alternative, the protective packaging machine110may be replaced by a device that does not create dunnage and instead simply conveys packaging articles, such as the packaging materials discussed above, to the main duct130of the conveyance system100. For example, instead of producing paper dunnage, the protective packaging machine110may be an inflatable cushion inflation and sealing device, the protective packaging machine110can create void fill articles or cushioning materials, or the protective packaging machine110can create envelopes, or any other suitable dunnage, packing peanuts, foam sheets, mailers, padded mailers or mailing or dunnage material or any other cushioning article, void fill article or paper-based packaging materials.

Referring again toFIGS.1and2, the conveyance system100includes a main duct130operably connected to the protective packaging machine110. The main duct130has at least one blower150operably connected to the main duct130to transport packaging articles from the protective packaging machine110to the receptacles122via airflow (e.g., an air stream) from the at least one blower150. As shown inFIG.1, the main duct130includes a packaging article inlet124that is connected to the outlet of the protective packaging machine110. The main duct130further includes one or more outlets134that correspond to one or more receptacles122. The receptacles122are configured to receive packaging articles from the protective packaging machine110through the main duct130. The packaging article inlet124connects the main duct130to the protective packaging machine110to receive the dunnage from the protective packaging machine110, preferably just downstream of the separating/cutting device. Packaging articles may be transported from the outlet of the protective packaging machine110through the main duct130to the receptacles122, as a result of airflow generated by the blowers150.

The packaging article inlet124may be arranged at a distance less than an anticipated length of the dunnage from the outlet of the protective packaging machine110. For example, the distance between the outlet of the protective packaging machine110and the packaging article inlet124may be less than about 100 cm, which is the anticipated maximum length of the dunnage. The airflow within the main duct130will tend to propel the articles through the main duct130, at least because in the present disclosure, the airflow enters the main duct130from at least two non-adjacent sides of the main duct130, which will energize a boundary layer adjacent to first and second side walls130a,130bof the main duct130, as described herein.

Referring toFIG.1, the main duct130extends in a longitudinal direction that corresponds to a direction which packaging articles travel through the main duct130. The main duct130may include a single section or a plurality of interconnected sections. As shown, the main duct130extends from the packaging article inlet124to at least an outlet (e.g., a first outlet)134that corresponds to one of the receptacles122. At least one of the blowers150is operably connected to the main duct130to generate airflow (e.g., an air stream) that enters the main duct130from at least two non-adjacent sides of the main duct130to propel the packaging articles through the main duct130.

The main duct130includes a first duct section131athat extends at an upward angle from the protective packaging machine110and defines a change in elevation. The first duct section131ais connected to a second duct section131bthat extends from the first duct section131ain approximately a horizontal direction. The second duct section131bis configured to extend over the receptacles122to distribute the packaging articles from the protective packaging machine110to the receptacles122. The main duct130additionally may include an elbow131cbetween the first duct section131aand the second duct section131b. As described with reference toFIG.9, the elbow131chas a greater height than other portions of the main duct130to prevent dunnage from being stuck against one or more walls of the main duct130as the duct transitions from the first duct section131ato the second duct section131b.

Optionally, the main duct130may additionally include a propelling device configured to assist in propelling packaging articles through the main duct130. For example, the propelling device may be a conveyor belt, a paddle wheel, a brush-type wheel mechanism or any other suitable device arranged within or adjacent to the main duct130to propel the packaging articles through the main duct130. Any such propelling device optionally may be included to generate an additional air stream to be added to the airflow in the main duct130at some point downstream of the blower(s)150. However, in the embodiment described herein, such a propelling device is not necessary to generate sufficient airflow to propel the articles through the main duct. Instead, according to the present disclosure, a suitable airflow is generated as the result of generating airflow in the main duct130by energizing the boundary layer in the main duct130, which is achieved by directing air streams from blower(s)150via two non-adjacent sides of the main duct130.

According to the present disclosure, the blower150(or multiple blowers150) is/are provided to generate the respective air streams through a blower duct section132(or a plurality of blower duct sections132), where the air stream(s) produce airflow that is configured to enter the main duct130to propel articles through the main duct130. In the embodiment depicted inFIGS.1-4, two blowers150are used in conjunction with the conveyance system100. However, any number of blowers150may be used, including a single blower or three or more blowers.

In the embodiment shown inFIGS.1-5, the main duct130includes first and second blowers150with corresponding blower duct sections132extending from the respective blowers150. Alternatively, it is possible to replace the first and second blowers150with a single blower in which an airflow is conveyed to at least two sides of the main duct130, e.g., circumferentially around the main duct130, or in which a plurality of air streams are branched from the single blower through respective blower duct sections132and conveyed to at least two sides of the main duct130.

Referring toFIG.3, the main duct130includes first and second blowers150arranged on non-adjacent sides of the main duct130, respectively, corresponding to the first and second side walls130a,130b. The first and second side walls130a,130bof the main duct130generally extend in the longitudinal direction. In particular, the first and second side walls130a,130bof the main duct130may be arranged generally opposite to each other. As shown inFIG.3, the main duct130may be rectangular in shape, and the first and second side walls130a,130bmay be arranged on opposite sides of the main duct130. Alternatively, the main duct130can be any other suitable shape, including but not limited to round, circular, oval, curved, trapezoidal, etc. The blowers150can be any suitable air moving device. The blowers150include an inlet150a(seeFIG.2) and blades150b(seeFIG.3) which pull air into the blower150through the inlet150aand push air out of the blower150through an outlet150c(seeFIG.3). The blower150includes an outer housing150dwhich houses the blades150b. The outer housing150dpreferably has a volute shape, but may be any other suitable shape such as rectangular, circular, etc.

The blowers150optionally may have multiple settings which can be changed depending, e.g., on the type, size, and density of the packaging article that is entering the main duct130from the protective packaging machine110. For example, the blowers150may utilize a higher power setting (e.g., a higher speed of airflow) for high density dunnage or packaging articles such as paper pads and a lower power setting (e.g., lower speed of airflow) for a lower density packaging article such as an inflatable cushion. The setting of the blowers150may be changed by the user at the control panel110aof the protective packaging machine110. Optionally, the conveyance system100may include systems which automatically detect and determine the dunnage and power setting for the blowers.

The blowers150are arranged to provide air streams on at least two non-adjacent sides (e.g., opposite sides) of the main duct130so as to produce an internal duct airflow to propel the packaging articles through the main duct130. The outlets150cof the blowers150are connected to the main duct130by the respective blower duct sections132. Each of the blower duct sections132has an opening132awhich receives the outlet150cof the blower150and decreases in size as the blower duct section132approaches a duct communication section132bwhich is connected to the main duct130, thereby increasing the velocity of the airflow at the duct communication system132bas compared to the airflow at the outlet150cof the blower150.

As provided herein, the blower duct sections132communicate with the main duct130at similar angles. However, the blower duct sections132may communicate with the main duct130at different angles. The air streams generated by the blowers150are transmitted through the blower duct sections132and generate airflow through the main duct130to propel the packaging articles from the protective packaging machine110through the main duct130.

The blower duct sections132are connected to the main duct130at the first and second side walls130a,130bof the main duct130such that the air from the blowers150contacts as much of the dunnage or packaging articles from the protective packaging machine110as possible. For example, if the protective packaging machine is being used to create pads of paper dunnage, the blowers150will be configured to contact as much surface area of the pads of dunnage as possible. As shown, the blowers150are positioned at the first and second side walls130a,130bof the main duct130such that the packaging articles from the protective packaging machine110may pass through approximately a center of the main duct130to prevent potential jams. Alternatively, a single blower could be attached to the main duct130at first and second sides of the duct via the blower duct sections132. Preferably the blowers150are arranged proximate the packaging article inlet124. Alternatively, the blowers150may be arranged downstream of the packaging article inlet124. Further, it is possible to position additional blowers150at other locations along the main duct130to provide more force from the air of the blowers150to keep the packaging articles moving through the main duct130.

Referring toFIGS.4A-4B, the duct communication section132bis configured to direct the air streams from the blowers150at an angle132crelative to one of the side walls130aor130bof the main duct130. As shown inFIG.4A, the angle132cis exemplary of an air stream entering the main duct130via approximately a center of the duct communication section132b, and is measured relative to a closest side wall130aor130bof the main duct130. Alternatively, the angle132ccan be measured as an angle between a longitudinal direction through a center of the blower duct section132and the longitudinal direction through the center of the main duct130. The angle132cshould not exceed about 90°, or more preferably, should not exceed about 60°. Therefore, any range of angles from about 0° to about 60° should provide suitable airflow to propel the articles. The angle132cshould be sufficient such that the airflow propels the articles through the main duct130without causing the articles to be caught or stuck in the first or second side walls130a,130bof the main duct130, or within the duct communication section132b. As shown inFIG.4B, an angle132dmay be measured between a side of the blower duct section132at the duct communication section132band one of the side walls130aor130bof the main duct130. The angles132cand132dinFIGS.4A and4B, respectively, are merely exemplary, and the angle of the airflow entering the main duct130from the blower duct sections132can be measured in any other suitable manner.

According to the present disclosure, by directing the airflow from the blower duct section132through the duct communication section132band into the main duct130, it is possible to propel articles through the main duct130. This is achieved, in part, by energizing the boundary layer142. In particular, a boundary layer is a thin layer of fluid (e.g., air) in the immediate vicinity of a boundary surface, i.e., formed adjacent to the side walls130a,130bof the main duct130by the fluid flowing along the surface. By introducing the airflow from the blower duct section132into the main duct130, it is possible to energize the airflow by adding momentum to the boundary layer, which enables the boundary layer142to stay on the surface of the side walls130a,130bfor a longer distance in the main duct130.

The boundary layer142is energized or enhanced by directing air streams into the main duct130from at least two non-adjacent sides of the main duct130. As compared to conventional air ducts, in which a single stream of air is directed into the duct, the present disclosure enables the airflow to move with sufficient velocity to propel the articles through the main duct130.

FIG.5shows a portion of an alternative main duct230according to the present disclosure. A blower duct section232is provided that is similar to the blower duct section132depicted inFIGS.3-4. However, the blower duct section232inFIG.5includes a door233. The door233can selectively block the blower duct section232to prevent airflow from the blowers from reaching the main duct230, or it can be closed partially to change the size of an opening at a blower duct communication section232bto partially restrict, accelerate, or aim the flow into the main duct230. For example, the door233may include a peg that slides longitudinally within a groove formed as part of the main duct230. Operation of the door233can be controlled at the control panel110a. Alternatively, the door can be moved on a hinge or other mechanisms. As a further alternative, rather than using a door, the blower(s) can be turned on or off to control airflow.

The main duct230is similar to the main duct130depicted inFIGS.3-4. The portion of the main duct230includes blower duct sections232which may be operably connected to one or more blowers in the same manner as the main duct130ofFIGS.3-4. The blower duct sections232include openings232a, which correspond to the openings132a(ofFIGS.3-4) and duct communication sections232bwhich correspond to the duct communication systems132b(ofFIGS.3-4). The duct232has first and second sides230a,230bwith one of the blower duct sections232arranged at either side. The main duct230has a first width233abetween the first and second sides230a,230bprior to where the blower duct sections232intersect the main duct230. Downstream of the blower duct sections232, the main duct230has a second width233bbetween the first and second walls230a,230b. The width of the main duct230in this embodiment increases in a step between the first width233aand the second width233b. The main duct230then may form a substantially constant width for the remaining portion of the main duct230. The blower(s) can be operably connected to the blower duct sections232, and to stop airflow, the blower(s) can be turned off.

Referring toFIG.6A, a piece of dunnage140is depicted inside a section of the main duct130. The piece of dunnage140is depicted as an article (e.g., a pad). Air pushes the dunnage140downstream through the main duct130, and as the dunnage140moves inside the main duct130, the energized boundary layer helps prevent the dunnage140from settling or getting pushed against a wall enough to get stuck, such as due to friction, or at a joint between components of the main duct130.

Referring toFIG.6B, the airflow within the main duct130exhibits a boundary layer142adjacent each of the side walls130a,130b, and the airflow has a velocity that is higher on outer portions (e.g., near the side walls130a,130b) as compared to a central portion between the side walls130a,130b. In addition, the internal airflow velocity and pressure can vary along various cross-sections of blower duct sections132and the main duct130. For example, the velocity of airflow within the blower duct sections132, especially in the duct communication section132bcan be higher than the velocity of airflow within the central portion of the main duct130. The difference in airflow velocity and pressure assists in forming the boundary layer142. InFIG.6B, exemplary streamlines represent airflow velocities through the main duct130. In particular, streamlines140depict airflow velocities through the blower duct sections130. As shown, the streamlines140being a wider distance apart represent slower velocities, whereas when the streamlines140are closer together, the velocities are faster. The airflow velocity as represented by the streamlines generally speeds up after the blower(s), and reaches a maximum in a neck area that corresponds to the duct communication sections132b. In the main duct130, the airflow velocity is faster in the boundary layer142. In particular, representative airflow velocities in the main duct130are shown at three exemplary cross sections141,143, and145. As shown, airflow velocities are relatively higher in the boundary layer142located at outer portions of the main duct130as compared to the central portion of the main duct130. This results from the boundary layer142being energized as a result of air streams being directed into the main duct130from at least two non-adjacent sides of the main duct130. Although every fluid flow adjacent a surface will exhibit a boundary layer, according to the present disclosure, the boundary layer is energized (i.e., the airflow velocity is accelerated) by generating the air streams from the different, non-adjacent sides of the main duct130, as compared to an arrangement in which only a single air stream is directed into a duct.

The velocity within the blower duct sections132according to the present disclosure can be approximately 5 to 20 m/s. The velocity in the duct communication sections132bcan be approximately 20 to 30 m/s. The velocity within the central portion of the main duct130may be approximately 8 to 10 m/s. The pressure within the outer portions of the main duct130near the side walls130a,130bmay be between 15 and 20 m/s.

The pressure within the blower duct sections132and the main duct130can be at or near atmospheric pressure of 101,325 Pa. For example, the pressure in the blower duct sections132may exceed atmospheric pressure by approximately 400 to 500 Pa. The pressure in the duct communication sections132bcan be within approximately 100 Pa of atmospheric pressure. The pressure within the central portion of the main duct130also can be between within approximately 100 Pa of atmospheric pressure. The pressure in the outer portions of the main duct130near the side walls130a,130bfurther can be between within approximately 100 Pa of atmospheric pressure

Referring again toFIG.1, the main duct130includes one or more outlets134where the packaging articles are released from. Referring toFIGS.7and8, the outlets134may include one or more diverters160. In particular, the outlet134is represented by the diverter160in an open position (seeFIG.7). The diverter160also may function as the main duct130when in a closed position (seeFIG.8). The diverter160may include a director wall162that is configured to open such that, when the director wall162is open, the packaging articles are directed through a path defined by the director wall162when it passes through the diverter160.

Referring toFIGS.7and8, the diverter160is depicted in a closed configuration and an open configuration, respectively. The director wall162of the diverter160is positioned on a rotating member164. The rotating member164may be configured to rotate so as to open or close the director wall162of the diverter160. Alternatively, the rotating member164could be replaced by a door with hydraulics that opens downwardly. The director wall162includes a flat surface162athat is configured to be flush with the main duct130when the diverter160is closed. The director wall162may include a director surface162bthat extends from a diverter side160ato a diverter side160bof the main duct130when the diverter160is in the open position. Alternatively, the director surface162bcould be fitted with an opening sized to permit dunnage to drop through the opening. While the director surface can be straight or have another suitable shape, in the embodiment shown, the director surface162bhas a curved surface that defines a smooth path for the packaging articles to travel. The diverter side160aincludes a notch168which is configured to receive the diverter when the director wall162is in an open position. The notch168prevents the director wall from being caught in the duct132. Alternatively, instead of the notch168, a mechanical latch or catch could be fitted in the diverter side160a.

The diverter160may be configured to be opened or closed manually by a user/operator. Alternatively, the diverter160can be controlled by an automated controller. Optionally, the diverter160is configured to open when a sensor determines that a receptacle is low on packaging articles (see further discussion below). For example, the packaging articles can be distributed by a controller based on fill levels detected by sensors. The diverter160may be configured to close when a sensor determines that a receptacle has enough packaging articles. Alternatively, instead of diverters160, an opening can be provided without a door.

Referring again toFIG.1, the main duct130includes multiple diverters160that act as outlets134, where the outlets134are configured to direct packaging articles to receptacles122. Each of the receptacles122optionally may include an internal divider so as to supply the packaging articles to separate workstations120, or the receptacles122may feed more than one of the workstations120. For example, the main duct130may include the same number of diverters160as receptacles122. Alternatively, the main duct130includes a different number of diverters160and receptacles122. In addition, the main duct130may terminate with a director166at the end of the main duct130that is configured to direct packaging articles into the last one of the receptacles122, and toward the last one of the workstations120. For example, if there are four workstation120, the director166would be positioned above the last/fourth workstation120. The director166is configured to operate similarly to the directors discussed above. Other configurations are additionally possible such as providing a snake conveyor instead of a receptacle.

In the example depicted atFIG.1, the conveyance system100includes three diverters160and the director166positioned over two receptacles122. Each of the receptacles122is configured to provide packaging articles to two workstations120. This configuration is exemplary, but any other configuration may be used. For example, it is possible to include an internal divider to partition each of the receptacles122into separate receptacles corresponding to the workstations120, respectively. In such an arrangement, each of the receptacles122would supply a single workstation120. Alternatively, it is possible for two diverters160to be arranged with respect to a single, unpartitioned receptacle122. The receptacles122are depicted as having an opening122bat the top to receive packaging articles (e.g., pads made of paper dunnage) from the duct132. For example, the duct can be opened or closed with a cover or any other desired top. This arrangement provides some flexibility, such that one or more of the workstations120associated with the receptacle122may be used at a given time, e.g., depending on current demand. Optionally, the director166may be permanently arranged in an open position. For example, as shown inFIG.1, the director166is configured to direct any remaining packaging articles from the main duct130to the last/fourth workstation120.

The packaging materials are directed into the receptacles122at each of the workstations120. The conveyance system100may include the same or a different number of receptacles122as outlets134or diverters160. In the example depicted inFIG.1, each of the receptacles122is associated with two workstations120, each of the workstations120being associated with an opening122afrom which packaging materials can be retrieved by operators for packaging and/or shipping operations. The receptacles122are adapted to store packaging materials until retrieved by an operator. The receptacles122may include one or more sensors that detect when packaging articles are received from the conveyance system100. In addition, each of the receptacles122may include a fill level sensor that detects when the receptacle has reached a full condition indicating that the receptacle is full or running low on packaging articles. For example, when the receptacles122are full of packaging articles, the protective packaging machine110can be switched off. Optionally, the director166, outlets134or diverters160can be opened or closed depending on the amount of packaging articles detected by the sensor and reopened when a predetermined fill level is detected by the sensors.

The conveyance system100may include a jam detection feature. For example, sensors of the receptacles122may detect each time packaging articles are received by the receptacles122. After a predetermined amount of time has passed and the receptacle has not received packaging articles, the conveyance system100may detect that a jam has occurred in the main duct130or elsewhere in the conveyance system100. Alternatively, different sections of the main duct130can be fitted with sensors which detect when packaging passes through the main duct130, and when packaging articles do not pass through the main duct130(e.g., detecting a jam). For example, the sensors can be photocells. Alternatively or additionally, the main duct130can include a clear section made from a material such as plexiglass such that an operator can see into the main duct130to determine whether the main duct130is jammed. The jam detection function can cause the conveyance system100to stop producing packaging articles.

The main duct130may be formed from a sheet metal material. In particular, the main duct130preferably is made from metal such as a malleable metal that is easily formed. For example, the main duct130may be formed from a material that is low-density such that it needs little support. The main duct130may be formed from an air-tight material or a flexible material. In particular, the main duct130may be formed from a material that includes some or all of the properties above. In one non-limiting example, the main duct130can be formed from an aluminum or an aluminum alloy material. As another example, as discussed above, portions of the main duct130can be formed from a transparent material such that a user can see within the main duct130. Optionally, a wall of the duct can be formed from a transparent material. For example, the wall can be formed from a material including but not limited to a plexiglass or glass. Alternatively, instead of a metal, the main duct130may be formed from various plastics or composite materials.

FIG.9is a view of an alternative main duct according to the present disclosure. Referring toFIG.9, a main duct330includes a first wall330aand a second wall330b. An elbow331cprovides a bend in the main duct330from a first duct section331athat extends in a first direction to a second duct section331bthat extends in a different, second direction at an angle to the first direction.

The first duct section331aand the second duct section331bhave similar heights333a. The elbow331cwidens between the first and second duct sections331a,331bto a height333bwhich is greater than a height333a. The wider height333bprevents dunnage from getting stuck within the elbow331cas the main duct330transitions between the first duct section331aand the second duct section331b.

The elbow331ccan be used, for example, in place of the elbow131cprovided in the main duct130as shown inFIG.1. While the elbow131cprovides a bend in the main duct130of about 60° (seeFIG.1), the elbow331cchanges the direction of the main duct330by approximately 90° from the second duct section331b(seeFIG.9). The elbow131cmay have the same cross-sectional height as the elbow331c. The elbows131c,331cas shown have straight inner walls. Alternatively, the inner walls of the elbows131c,331cmay widen, i.e., have wider cross-sectional heights. As a further alternative, instead of an elbow with a greater height than first and second duct sections, it is possible to provide an elbow or bend with a constant cross-sectional, radial height about the bend that corresponds to the height of each of the first and second duct sections131a,131bor331a,331b.