Method and Apparatus for Stackable Totes with Conditioning Features

This Application is a Non-Provisional Application U.S. Application Ser. No. 63/651,421, filed May 24, 2024, the content of which is incorporated by reference in its entirety.

This invention relates generally to stackable totes or other holders, e.g., that can heat and/or cool or otherwise condition contents in the tote.

The inventors have appreciated that systems and facilities for storing and handling items, including items that are to be maintained at temperatures above and/or below ambient temperatures, have drawbacks particularly when the items are handled by robotic or other automated handling systems. For example, items that must be maintained in a frozen or otherwise cooled conditions (e.g., temperatures below 0 degrees C.) are typically stored in boxes or crates that are stacked in a cooled space in a warehouse. While these conditions may be suitable to keep the items at a suitably low temperature, the cooled warehouse space can be damaging to equipment operating in the cooled space and/or uncomfortable to people in the cooled space. For example, equipment operating in the cooled space may be exposed to temperatures that are below ideal operating temperatures (e.g., temperatures low enough to cause lubricants to be less effective) and/or that cause condensate to form on portions of the equipment (e.g., water may condense on electronics or other components that are sensitive to moisture). Thus, systems, apparatus and methods that permit items to be stored and/or handled at temperatures above and/or below ambient temperatures without requiring the use of a heated or cooled warehouse space are desirable.

In some embodiments described herein, items may be stored in non-ambient conditions (e.g., temperatures above and/or below ambient temperatures, at humidity levels above and/or below ambient, etc.) within totes or other containers that are located in a warehouse or other space that has ambient conditions (e.g., temperature, humidity and/or other aspects) that are not controlled at all or not controlled in a way suitable for the stored items. Such systems and methods may also allow for items to be stored and/or manipulated in a warehouse or other space while the items in different totes are maintained in different temperatures or other conditions. Thus, items stored in a frozen state may be stored within totes located in a same warehouse space as items that are refrigerated but maintained at temperatures well above freezing in other totes. This arrangement may also allow equipment, such as robots or other automated manipulation equipment, that move or otherwise manipulate the totes to operate in ambient or other conditions that are best suited, or at least more suitable, for the equipment. As an example, robotic manipulating equipment may operate to move totes in conditions that reduce the likelihood of condensate forming in or on the equipment and/or that do not inhibit the proper operation of lubricants or other equipment components. Human operators may also be permitted to work in the warehouse or other space where totes are stored in an environment more suited to human habitation.

In some embodiments, totes may be configured to receive conditioned gas from a separate source, e.g., a gas conditioning system such as a refrigeration system or heater, and multiple totes may receive conditioned gas from a common gas conditioning system. Thus, some embodiments may provide for conditioning of the interior space of totes (and items in the interior space), including the internal space of multiple totes, without requiring the totes to include individual heating, cooling or other systems. Rather, the totes may include no or few moving parts and/or complicated and expensive systems to control the environment within the internal space of the tote. The totes may therefore be made relatively inexpensively, lighter in weight, have a larger interior space and/or require little or no power for storing items in a desired environment in the tote.

In some embodiments, a tote for holding items may include a container body having a bottom wall and at least one sidewall (e.g., three or four sidewalls) extending upwardly from the bottom wall to an upper end that defines an interior space configured to hold items. For example, a tote may have a rectangular bottom and four sidewalls that together define a cuboid volume, or may have three sidewalls and a top wall configured so the interior space of the tote can be accessed from the side rather than the top. A lid or door may be provided to cover an opening to the interior space, e.g., to enclose the interior space in an airtight or other manner, and the lid or door may be attached via a hinge or other mechanism, e.g., so the lid or door can be moved between open and closed positions while remaining attached to the tote. The bottom wall and/or sidewalls and/or door or lid may be insulated or otherwise configured to reduce heat transfer and/or gas transfer between the interior space and an exterior environment. A duct may be supported by one or more sidewalls, e.g., a duct may extend within a sidewall from the bottom wall to the upper end of the sidewall, and be configured to conduct flow of gas through the duct, e.g., from the bottom wall to the upper end. A tote may include only one duct, or may include two or more ducts, whether in one sidewall or in two or more sidewalls if the tote includes more than one sidewall. In some cases, a tote may have two ducts, e.g., on opposite sides of the interior space, to support flow of conditioned gas into the interior space from one duct and out of the interior space to another duct. A conditioning feature may be configured to use air in the duct to condition the interior space relative to an exterior environment. For example, the conditioning feature may be configured to exchange heat and/or other conditions between the duct and the interior space to heat, cool or otherwise condition the interior space relative to an exterior environment. For example, chilled, dried, humidified, heated or otherwise conditioned air may be caused to flow through the duct and conditioning feature may use the conditioned air to operate on conditions in the interior space. In some cases, the conditioning feature may fluidly couple the interior space and the duct, e.g., so air can flow from the duct into the interior space and/or from the interior space into the duct. In some cases, the conditioning feature may not permit fluid flow between the interior space and the duct, e.g., a heat sink or other component may exchange heat between the duct and the interior space without air exchange between the duct and interior space. A conditioning feature that conditions the interior space without air or other exchange with the interior space may permit a particular environment, such as an oxygen-reduced, low humidity, etc. environment, to be maintained in the interior space.

In some cases, a tote may be configured to be stacked on another tote and/or to have other totes stacked on it. For example, the bottom wall of the tote may include a locating recess in the bottom wall configured to engage with a locating protrusion of a second tote, e.g., on which the tote is stacked, to position the second tote relative to the bottom wall. In some embodiments, the bottom wall may include a bottom opening to the duct, and the bottom opening may be positioned within the locating recess.

In some embodiments, the upper end of the at least one sidewall may include a locating protrusion extending from the upper end and configured to engage with a locating recess of a second tote, e.g., that is stacked on the tote, to position the second tote relative to the at least one sidewall. In some cases, the upper end may include an upper opening to the duct, and the upper opening may be positioned at an uppermost portion of the locating protrusion.

A conditioning feature may be arranged in different ways, may include one or more different components and may be provided for each duct a tote has. In some cases, a conditioning feature may include one or more openings in the at least one sidewall configured to permit gas flow between the duct and the interior space, e.g., so conditioned gas in the duct can flow into the interior space and/or so gas in the interior space can flow into the duct. In some embodiments, a tote may have a first sidewall with a first duct and a second sidewall and a second duct defined by the second sidewall. The second duct may extend from the bottom wall to the upper end of the second one sidewall and be configured to conduct flow of gas through the second duct. In some cases, a conditioning feature may be provided for the second duct, e.g., one or more openings in the second sidewall configured to permit gas flow between the duct and the interior space. The first and second sidewalls may be at opposite ends of the interior space, e.g., to support conditioned gas flow across the interior space from the first sidewall to the second sidewall.

In some embodiments, a conditioning feature may include an air mover, such as a fan, to move air through the one or more openings and/or to resist air movement through one or more openings.

In some cases, a conditioning feature may include a heat exchanger, e.g., a finned heat sink, having a first portion positioned in the duct to exchange heat with gas in the duct, and second portion positioned in the interior space to exchange heat with gas in the interior space.

In some embodiments, a lid or top wall may be provided to engage with the upper end of the at least one sidewall to enclose the interior space, and the lid or top wall may include a lid duct in fluid communication with the duct. In some cases, a tote may include two ducts and the lid may be configured to fluidly couple the lid duct with both ducts of the tote, e.g., so conditioned gas can flow from one duct, through the lid duct and to the other duct of the tote. In some cases, a lid may close one or more ducts of a tote, e.g., so that air flow from an upper opening of the duct is prevented by the lid. Such an arrangement may force air flow from a duct into an interior space and/or out of an interior space into a duct.

As noted above, totes may be configured to be stacked on each other, and thus a second tote may be provided that is configured similarly to a first tote (e.g., having any of the features described herein), and both totes may be configured for stacking on each other. For example, a second tote may be positioned over a first tote such that the bottom wall of the second tote is on the upper end of the at least one sidewall of the first tote, and such that the duct of the first tote is in fluid communication with the duct of the second tote. Totes in a stack may have the same, or different features, e.g., different interior space sizes, different conditioning features, etc. In some cases, a tote may include a damper, e.g., at the bottom wall and/or at the upper end, configured to open and close a respective duct. The damper may be configured to closed when a tote is not mated with another tote or a base unit and to open the duct when a tote is mated with another tote or base unit, e.g., so that the ducts of the two totes can communicate with each other. Thus, if a tote is not mated with another tote, the damper may close the duct. In some cases, the damper may be configured to open passively, e.g., with contact of a second tote with the damper. For example, when a second tote is placed over a tote, a damper at the upper end may be contacted by a portion of the second tote to move the damper to an open position.

In some embodiments, a base unit may be provided with an upper surface configured to engage with the bottom wall of a tote and support the tote on the base unit, e.g., the tote may be stacked on the base unit, and additional totes may be stacked on the tote. The base unit may include a gas supply opening in fluid communication with the duct of the tote and configured to provide heated, cooled or otherwise conditioned gas to the duct. In some cases, the base unit may include a gas return opening in fluid communication with a second duct of the tote and configured to receive gas from the second duct. For example, conditioned gas provided to a first duct of the tote by the gas supply opening may flow through the tote (or other totes in a stack) and return to the gas return opening of the base unit via the second duct of the tote. In some embodiments, the base unit may include a heating and/or cooling unit configured to heat and/or cool gas received from the second duct at the gas return opening and provide heated and/or cooled gas to the first duct via the gas supply opening. A base unit may include a locating protrusion on an upper surface to interact with the tote stacked on the base unit, e.g., the bottom wall of the tote may include a locating recess configured to receive and engage with the locating protrusion to position the tote relative to the base unit. Various exemplary embodiments of the device are further depicted and described below.

Inventive features are described below with reference to illustrative embodiments, but it should be understood that inventive features are not to be construed narrowly in view of the specific embodiments described. Thus, aspects of the invention are not limited to the embodiments described herein. It should also be understood that various inventive features may be used alone and/or in any suitable combination with each other, and thus various embodiments should not be interpreted as requiring any particular combination or combinations of features. Instead, one or more features of the embodiments described may be combined with any other suitable features of other embodiments. For example, one embodiment is described in which totes include at least one duct to permit gas flow through a portion of the duct (e.g., for heating or cooling) and include a locating feature adjacent an opening to the duct. These features may be used together as in the embodiments below, or independently of each other. For example, a tote may include a duct with various features described herein, but not include a locating feature at all, or include a locating feature that is not adjacent to an opening to the duct. Similarly, a tote may include a locating feature configured as described herein, but not include a duct at all for gas flow through a portion of the tote. These are merely two examples, but the point is that aspects described below can be used in any suitable combination, at least to the extent not mutually exclusive.

In some aspects, two or more totes may hold items in a non-ambient environment and may share a common a common source of conditioned gas (e.g., heated and/or cooled air, humidified and/or dehumidified air, and so on). As an example, a single refrigeration system may be used to provide conditioned gas to two or more totes, e.g., to cool items held in all of the totes. In some cases, the common source of conditioned gas may have only one conditioned gas outlet, and all of the totes may be connected to the single conditioned gas outlet. For example, a first tote may be connected to the conditioned gas outlet, and other totes may be connected directly or indirectly to the first tote to receive conditioned air. This is in contrast to systems that require each tote to be individually connected to a conditioned gas supply.

In some aspects, a first tote may include a duct configured with an inlet to receive conditioned gas and an outlet to output conditioned gas. A second tote may include a duct configured with an inlet to receive conditioned gas, and the inlet of the second tote may be fluidly coupled to the outlet of the first tote, e.g., so the second tote can receive conditioned gas from a source of conditioned gas that is fluidly coupled to the inlet of the first tote. This can permit both totes to receive conditioned gas from a single source and without requiring all of the totes to be directly coupled to the source of conditioned gas. Rather, the second tote can be indirectly coupled to the source of conditioned gas via the first tote. This arrangement can allow for an expandable and scalable storage arrangement, e.g., where 3, 5, 10 or more totes are all coupled to a single source of conditioned gas via a single one of the totes. In some cases, the totes may be stacked, one on the other and so that conditioned gas may flow through the stack to each of the totes. In some cases, flow of conditioned gas through the totes may be in a closed loop such that gas provided at the conditioned gas supply is provided to one or more totes and then returns to the source of conditioned gas, e.g., to be cooled and returned to the totes as needed. As a result, the environment in the interior space of the totes can be controlled in a desired way that is different, including potentially drastically different, from a warehouse or other ambient environment in which the totes are located.

shows an illustrative embodiment of an item handling systemthat includes a plurality of totesthat may each include an interior space to hold one or more items, such as food items, machine parts, consumer goods, etc. The totes I may be stacked on top of each other as shown and each stack may include any suitable number of totes, including one or more. Thus, althoughshows four totesin a stack, a stack may include any number of totes. In some cases, the totesmay be stacked on a base unit, which may provide physical support to the totesand/or function as a source of conditioned gas that is provided to the totes(e.g., to heat, cool, humidify, dry, etc. items in the totes). In some cases, the base unitmay include a gas conditioning system, such as a refrigeration unit configured to chill air, a heater to heat air, a dehumidifier unit to remove moisture from air, a gas source to provide a reduced oxygen gas to totes, and/or other components to otherwise condition air. The base unitmay itself include all components of a gas conditioning system, such as one or more controllers, pumps, refrigerant compressors, heating elements, evaporator coils, condenser coils, gas supplies, etc., or may include less than all components of a gas conditioning system, such as only an evaporator coil that is fluidly coupled to receive refrigerant from a remotely positioned compressor, condenser, controller, etc. and is configured to provide chilled air to a stack of totes. Thus, multiple base unitsmay be coupled to common components of a gas conditioning system, such as a compressor and condenser that provide compressed and cooled liquid refrigerant to evaporator coils at each of multiple base units, since a base unitneed not include all components required of a gas conditioning system. Electrical and other power may be provided to a base unitas required.

As shown in, an uppermost totein a stack may have a lidthat engages with the upper portion of the toteand closes an interior space of the totewhere items may be held. Toteslower in the stack may have their respective interior space enclosed by a totethat is immediately above, e.g., a bottom wall of an upper totemay engage with the upper portion of a lower toteto enclose the interior space of the lower tote. Alternately, toteslower in the stack may have their interior spaces closed by a lid, and the lidmay provide a fluid connection between ducts as needed. Suitable sealing elements such as gaskets, etc. may be provided at the interface between totesas desired. As can be seen in, the lidon an uppermost totemay be removed, e.g., to allow for access to the interior spaceof the toteand/or to permit another toteto be placed on top of the stack. Each of the totesand/or the lidmay be configured to be manipulated by any suitable robotic or other handling system, and/or may be configured to be manipulated by hand by human operators. Totesmay include a manipulation featuresuitable for engagement with a robotic or other machine manipulator and/or by a human operator. A manipulation featuremay include a handle, groove, lip, magnetic element, hook, opening, or any other suitable feature, and may be located in any suitable place or places on a tote(i.e., is not limited to the location shown as an example in).

illustrates how multiple totesin a stack can receive conditioned gas from a single base unitor other source of conditioned gas. In some embodiments, the base unitincludes an outlet for conditioned gasand an inlet for conditioned gas, e.g., so the base unitcan provide cooled or otherwise conditioned gas to an inletof a ductof a toteimmediately above the base unitand can receive conditioned gas from the totevia another ductthat is fluidly coupled to the inlet for conditioned gas. Conditioned gas provided to the inletof the lowermost totecan flow upwardly through the ductsof each of the totesin the stack which are fluidly coupled together. Optionally, the conditioned gas may flow through a ductof the lidand then flow downwardly to the inlet for conditioned gasvia ductsof the stacked totes. (Note that a lidneed not include a ductand may simply enclose an uppermost tote.) As a result, cooled or otherwise conditioned gas may flow across at least portions of totesin the stack, e.g., along portions of a ductto cool the interior spaceof the totes. Walls of the totes(including lids and/or doors) may be insulated and/or otherwise configured to minimize heat transfer and/or gas exchange between the interior spaceand an exterior environment. However, portions of a sidewall between a ductand the interior spacemay be configured to maximize (or minimize or otherwise control) heat exchange and/or gas exchange with the interior spaceand the duct.

In some cases, one or more totesmay include a conditioning featureconfigured to exchange heat between the duct and the interior space to heat or cool or otherwise condition the interior spacerelative to an exterior environment, e.g., an environment in which the totesare stored. The conditioning featuremay be configured in any suitable way and include any suitable component or components. For example, a conditioning featuremay include one or more openings in a sidewall of the toteto permit fluid communication between the ductand interior spaceof the tote. That is, conditioned gas in the ductmay flow through the openings of the conditioning featureand into the interior space. Gas in the interior spacemay exit via openings of another conditioning featureon an opposite or other sidewall of the tote, e.g., to enter a ductand return the gas to the inlet for conditioned gasat the base unit. Alternately, gas may be simply vented from the interior spaceafter being used to suitably condition the interior spaceof a tote, e.g., via openings or other pathways that permit air in the interior spaceto exit to a surrounding environment. Thus, totesneed not necessarily have two or more ducts, but may have only one duct, e.g., that provides conditioned air into the interior spaceof a totewhich vents air from the interior space. In some cases, a conditioning featuremay include an air mover, such as a fan, to assist or otherwise control gas flow from a ductinto and/or out of an interior spaceof a tote. In some embodiments, a conditioning featuremay include a flow control device, such as a damper, valve, etc., to control flow of gas into and/or out of an interior spaceof a tote. Such conditioning featuresmay be controlled by an electronic controller (e.g., a computer-based controller including one or more sensors, actuators, power supplies, etc. to effect control operations), a thermo-mechanical controller (e.g., a bimetallic actuator and baffle or valve) and/or manually (e.g., by a human operator). In some cases, a conditioning featuremay be configured to exchange heat between a ductand an interior spaceof a totewithout gas exchange between the ductand interior space. For example, a conditioning featuremay include a finned heat sink, heat pipe, or other component configured to move heat between the ductand the interior spacewithout gas exchange between the ductand interior space. For example, a finned heat sink may have fins exposed to gas in a ductand fins exposed to gas in the interior space so that heat can be moved between the ductand the interior spacewithout gas exchange. Such an arrangement may be useful when it is desired to not exchange air with the interior spaceof a tote, e.g., to maintain a low oxygen environment, to help prevent drying of items in the interior spaceby chilled air, etc. Thus, a conditioning featuremay include passive and/or active elements to exchange heat between a ductand interior space, and may permit, or not, gas exchange between the ductand interior space. As needed, power may be provided to a conditioning featureby a battery or other supply, such as an electrical connection to the base unit(whether through one or more intervening totesor by direct connection to the base unit). As an example, electrical contacts at top and bottom surfaces of totescan make electrical contact with totesabove and below so as to conduct electric power and/or communications between totesand/or a base unit.

As noted above, where a conditioning featureprovides for gas exchange between a ductand an interior spaceof a tote, a flow rate and/or volume of gas flow into and/or out of the interior spacemay be controlled actively and/or passively. For example, one or more openings of a conditioning featuremay be sized and/or otherwise arranged to provide a desired flow of gas into and/or out or the interior spaceof a tote, and/or a fan may be operated to provide desired flow, e.g., to achieve a desired temperature in the interior spaceas detected and controlled by a controller of the conditioning featureand/or a gas conditioning system. Flow control elements, such as baffles, louvers, dampers, valves, etc. may be provided in one or more ductsand/or in an interior spaceto provide desired flow characteristics, such as pressure drop, flow rate, flow volume, turbulence, etc. in various portions of the gas flow system. In some cases, a ductof a lidmay include one or more flow control elements, whether actively controlled or passive in operation, to provide a desired pressure drop or other flow characteristic across the interior spacesof totesin a stack. In some cases, flow through one or more totesmay be different from that through one or more other totes, e.g., so that different storage temperatures are provided in different totesof a stack.

In some cases, a base unitand/or gas conditioning systemmay include the ability to detect a number of totes that are coupled to the gas conditioning systemand adjust its operation accordingly. For example, as shown ina gas conditioning systemmay include a refrigeration system having a condenser, compressorand evaporatorconfigured to cool air that is circulated with respect to totesstacked on the base unit. As will be understood, operation of the gas conditioning systemmay need to be adjusted based on a number of totesrequiring conditioned gas, e.g., a gas flow rate, heat removal rate, and/or other characteristics of the gas conditioning systemmay need to be adjusted to accommodate different numbers of totesor varying requirements of totes. For example, if contents in the totesmust remain at freezing temperatures, the gas conditioning systemmay need to operate differently than if the contents are to be maintained at chilled but above freezing temperatures. In some cases, a gas conditioning systemmay include one or more sensors to detect a number of totes coupled to the gas conditioning systemand control its operation accordingly. For example, totesmay include an RFID tag or other wireless or wired communication device to communicate with a controller of the base unitand/or the gas conditioning systemto indicate the tote'spresence and/or conditioning requirements for the tote's contents (e.g., gas flow rate, internal temperature, humidity level, etc.). For wired communication, totes may include electrical contacts at top and bottom surfaces of the tote and suitable wiring to establish electrical connections with totes above and/or below and a base unit, e.g., so a controller of the base unitcan communicate with all totes in a stack. In some cases, a gas conditioning systemmay be configured to detect a number of totes in a stack based on gas flow or other characteristics of gas moved with respect to a stack of totes. For example, the gas conditioning systemmay include a pressure sensorpositioned downstream of the evaporator, e.g., downstream of an evaporator fan that is positioned downstream of the evaporator, to measure the pressure at the exit of the evaporator fan. The pressure at this location may relate to the pressure drop of the entire air circulation system including flowpaths through the totesand the number of totesin the stack. From this measured pressure, the gas conditioning systemmay infer the number of totesin the stack and allow improved control of the conditioning system and the air flow rate around the circulation loop. In some cases, a temperature sensor may be positioned in the return air duct, e.g., near the inlet for conditioned gas, to indicate whether the conditioned gas circulation loop is sealed or whether ambient air is entering the circulation loop due to a mis-positioned tote or a missing toteor lid. For example, a higher than expected temperature or unexpected pressure drop for the circulation flowpath may indicate a leak caused by a misaligned tote, lid or other problem. Information from these and/or other sensors may be used to control various aspects of the gas conditioning system, such as circulating fan speed, heater current, refrigerant compressor operation, etc. Alternately or in addition, a controller of the gas conditioning systemmay provide alerts or other information to a user or other system components regarding a detected problem, e.g., a robotic manipulator may be alerted to replace or position a totethat is suspected to be mispositioned.

As can be appreciated fromand seen in, in some cases a totemay include a container body having a bottom walland at least one sidewall(e.g., four sidewalls in a rectangular configuration) extending upwardly from the bottom wall to an upper end. (Note that a totecan have any number of sidewalls, such as one circular sidewall, three sidewalls that define a side opening to the interior space, etc.) The bottom walland the sidewallsdefine the interior space, and the ductsare each supported by a sidewallwith the duct extending from the bottom wallto the upper end of the sidewall. In some cases, a sidewallmay define a duct, e.g., a ductmay extend through an inner space of a sidewall. In some cases, a ductis not defined by a sidewalland instead may extend along an inner and/or outer surface of a sidewall, e.g., a tube defining the duct may be attached to a sidewall portion. Openings at the bottom walldefine an inlet or outlet to a ductand openings at the upper end of the sidewalldefine an inlet or outlet to a duct. This configuration allows totesto be stacked one on top of another while fluidly coupling the ductsof the totestogether. Where a totehas two or more ducts, the ductsmay be used for different purposes. For example, one ductmay be used for air exchange with an interior spaceof a tote, e.g., for humidifying or drying, and another ductmay be used non-air exchange chilling or other conditioning.

In some cases, totesmay include locating features at upper and lower surfaces to aid in locating totesrelative to each other when the totesare stacked and/or to help keep totesin a desired position relative to each other after stacking is complete. As an example, a totemay include a locating recess formed in a portion of a bottom walland a locating protrusion formed on a portion of an upper surface of a sidewall. When such totesare stacked, the locating protrusion on a lower totemay engage with the locating recess on the upper tote, and thereby position the totesrelative to each other. In some cases, locating features may be useful in positioning toteswhen stacked by a robot or other automated handling system. For example, if a robot is required to position a totevery accurately when stacking the toteon another tote, the robot may need to move relatively slowly and/or have highly capable (and expensive) control systems to achieve highly accurate tote placement. In some cases, locating features on totes I may relieve at least some of the accuracy requirements placed on automated handling systems when stacking totes, e.g., because the locating features may engage with each other during toteplacement so that the locating features guide movement of the totes I relative to each other. As a result, automated handling systems may need only place totesin a generally accurate, but not highly precise way when stacking.

show example arrangements for locating features that may be employed with totes. As can be seen in, the upper end of the at least one sidewallmay include a locating protrusionextending from the upper end. As can be seen in, the bottom wallmay include a locating recessconfigured to engage with a locating protrusionof a second tote, e.g., on which the toteis stacked, to position the totes relative to each other. While the locating protrusionand locating recesscan be configured in various ways, the locating protrusionmay be configured to have a tapered or other shape that generally widens in at least one dimension in a top-down direction. As an example, a locating protrusionmay have a generally pyramid or other conic solid shape. Such a shape may help move totes in horizontal directions as the totesare engaged with each other. Similarly, a locating recessmay have a shape that is complementary to the shape of a locating protrusionwith which the locating recessis to cooperate, e.g., a recess with a conic solid shape. Althoughshow an arrangement in which a locating protrusionis positioned on an upper end of a sidewalland a locating recessis positioned at a bottom wall, the positioned of the locating features may be reversed. However, providing a locating recesson a bottom wallmay permit the toteto be placed on a solid, flat surface while spreading the weight of the toteacross the entire bottom wallrather than focusing the weight on one or more locating protrusions. Regardless, any suitable position for locating features can be employed.

In some cases, a ductmay extend between a locating recessand a locating protrusion. For example, the bottom wallmay include a bottom opening to a duct, and the bottom opening may be positioned within a locating recessas shown in. Likewise, an upper end of a sidewallmay include an upper opening to a duct, and the upper opening may be positioned at an uppermost portion of a locating protrusion. Such an arrangement is shown in. This arrangement may help properly locate totesrelative to each other while ensuring that ductsof stacked totesare in proper fluid communication with each other. As can be seen in, a base unitor other support for a stack of totesmay similarly include one or more locating features such as a locating protrusionto help position a toteon the base unit. Openings for the outlet for conditioned gasand an inlet for conditioned gasmay be provided through the locating protrusions, e.g., to fluidly couple the openings to ductsof a tote. Similarly, a lidmay include a locating feature such as a locating recessas shown into help properly locate a lidon a toteand fluidly communicate a ductof the lidwith ducts of a tote. Note that a lidmay include locating protrusions and/or recesses, e.g., to aid in alignment of the lid with a tote, but the lidneed not include a duct. Instead, the lidmay function to close one or more ductsof a toteon which the lidis placed. Not as well that ductsmay be separate from locating protrusionsand/or recesses, although engagement of such locating features may help align ducts of two totes relative to each other for suitable fluid coupling.

In some cases, totes may have one or more openings by which to access the interior space of a tote. In some of the embodiments above, totes have one or more sidewalls that extend upwardly from a bottom wall to define a top opening by which the interior space is accessed. However, other, or additional, configurations are possible for providing an access opening for totes. For example, a sidewall can be omitted and/or one or more openings may be provided in a top wall and/or sidewall through which the interior space may be accessed. For example,shows an embodiment in which totesinclude a bottom wall, three sidewallsand a top wallthat define a side opening to access the interior space. In some cases, a top wallmay include locating features like those discussed herein, e.g., one or more locating protrusionsand/or recesses. An opening to a ductmay be provided at the upper end of the sidewall so the opening is exposed at the top wall. Thus, the ductsof stacked totesmay fluidly communicate in the same way as in. One or more doorsmay be provided to open and close the opening to the interior spaceof totes. In some cases, a doormay be mounted to a toteby a hinge or other mechanismthat allows the doorto be moved between an open position, as shown in, and a closed position in which the side opening to the interior spaceis closed. Such an arrangement may allow totesin a stack to have their interior spaceaccessed without requiring that the totebe removed from a stack. That is, a doormay be opened and closed while a toteis positioned in a stack. A doorof a totemay be moved independently of other doors of totesin a stack, or doorsof totesin a stack may be moved together, e.g., to access all of the interior spaces of totes in a stack at a same time. Suitable seals, gaskets or other sealing arrangements may be provided to allow the doorto close the interior spacein a desired way, e.g., a magnetic seal like that found in refrigerators may be provided with a door. A latch or other mechanismmay be provided to lock the door in a closed and/or open position. A doormay be provided for a totein any suitable location and in any suitable way. For example, if totes have sidewalls that define a rectangular interior space, a doormay be provided on a long side of the tote as inand/or on a short side of the tote and/or at a top wall and/or in other locations.

In some cases, a tote may include a damper to open and/or close a duct, e.g., at a bottom wall and/or at an upper end of a sidewall. This may permit a duct to be closed, e.g., to prevent air flow from the duct, to prevent dirt or other contaminants from entering the duct, and/or to avoid the need for a lidlike that shown in. For example,show an embodiment in which a tote includes a damperthat can selectively open and close a duct. In this embodiment, the damperis located at an upper end of a sidewall at a top wallof a tote, but such a damper can be positioned in any suitable location, such as an upper end of a sidewall of a tote having no top wall, at a bottom wall, etc. In some cases, the dampermay be configured to open in response to mating of a tote with another tote and/or a lid, e.g., so that the ducts of the two totesor lidcommunicate with each other.show such an arrangement in which the dampermay move from a closed position shown into an open position shown into allow communication with the duct. In some cases, a portion of a mating totemay cause a damperto move between open and closed positions. For example, a protrusionon a mating toteor lidmay contact the damperand move the damperto an open position. A protrusionmay extend downwardly from a bottom wall of a tote, e.g., the protrusionmay be located in a ductof a mating tote, and may be configured to contact a damperand move the damperso as to open the duct. In some cases, a dampermay be resiliently biased to move to a closed position, and contact of a protrusionor other portion of a mating totemay move the damperagainst the resilient bias. For example, a dampermay include a plate, e.g., of metal or other material, that is mounted by a hinge to a tote sidewall, top walland/or bottom wall, and the plate may be biased by a spring to move to the closed position. In some cases, a dampermay be moved by a powered mechanism, such as a drive motor or other actuator.

As described above, a gas conditioning systemmay be configured to detect a number of totes or other characteristic of a stack of totes.shows an embodiment of a base unitthat includes a stack size sensorconfigured to determine a number of totes in a stack or other size characteristic of a stack. Based on such information, the gas conditioning systemmay adjust its operation as discussed above. In some cases, the stack size sensormay include a distance measuring device, such as a laser distance measuring device that uses a time of flight of a laser signal to determine distance, that can measure a length of a pathway defined by one or more ducts of a stack of totes. As an example, the stack size sensormay direct a measuring laser upwardly into ducts of totes stacked on the base unit. The measuring laser may be reflected by a damper, lidor other component located at an upper end of a series of ductsand allow the stack size sensorto determine a length of the duct or combined ducts. Based on the duct pathway length, the gas conditioning systemcan determine a number of totes in the stack, a total volume of interior space of the stack to be conditioned and/or other size characteristics of the stack. Based on this information the gas conditioning systemcan make suitable adjustments to operation. A distance measuring device may be useful with totesthat include a damperat an upper end of a sidewall and/or at a top wall that open in response to mating with another tote. That is, only a damperat an upper most position in a stack will remain closed because others will be opened by mating totes, and the distance measuring device can measure the distance to the upper most damper, thereby determining the size of the stack. Although the stack size sensoris shows outside of an expansion plenum, e.g., so as to emit a measuring laser through a window and into the ducts, the stack size sensorcould be located inside of the plenumor other ductwork of the gas conditioning system.

also shows an exemplary air flow through the gas conditioning system, although other arrangements are possible. Air from a duct of a toteover the base unitcan enter in a generally downward direction through an inlet for conditioned gas, and travel through an evaporator, e.g., for chilling and/or dehumidifying air. Moisture removed from the air may be removed from the flowpath via one or more condensate drains, e.g., in the evaporatorand/or in an expansion plenum(which may allow chilled air to expand and therefore further cool, releasing further moisture in the process). The chilled and/or dehumidified air may exit the base unitvia the outlet for conditioned gasand flow into the ductof an overlying tote. This is just one example of how gas may be conditioned by the base unitand it should be understood that any suitable conditioning may be employed.

shows how air flow may occur in a stack of totesincluding two totesand a base unitin an illustrative embodiment. In some embodiments, totesmay include conditioning featuresin the form of one or more openings that permit air exchange between a ductand the interior spaceof the tote. In, both toteshave such conditioning features. A lidis provided to enclose the interior spaceof the uppermost tote, and may optionally close the ductsof the uppermost tote, e.g., if the totedoes not have a damperto close the ducts. Closing of the ductsby the lidmay help encourage air flow from a supply flowprovided by the base unitinto ductsof the totes, into and across the interior spaceof both totes, and into a return flowthat flows through ductsof the totesback to the base unit. As noted above, flow through the interior spacesmay be controlled in any suitable way, such as by dampers, etc. Control of any system components, such as a conditioning feature, gas conditioning system, etc., may be performed by any suitable control circuitry of one or more controllers, which may include a programmed general purpose computer and/or other data processing device along with suitable software or other operating instructions, one or more memories (including non-transient storage media that may store software and/or other operating instructions), a power supply for the control circuitry and/or other system components, temperature and liquid level sensors, pressure sensors, RFID interrogation devices or other machine readable indicia readers (such as those used to read and recognize alphanumeric text, barcodes, security inks, etc.), input/output interfaces (e.g., such as the user interface to display information to a user and/or receive input from a user), communication buses or other links, a display, switches, relays, triacs, motors, mechanical linkages and/or actuators, or other components necessary to perform desired input/output or other functions.

While aspects of the invention have been shown and described with reference to illustrative embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.