Telescoping dunnage rack

A transportation rack includes a base frame configured for resting on a surface and including an upper open side and an open front side. The transportation rack further includes an extension frame defining an open front side and being slideably received through the open upper side of the base frame. An actuator is coupled between the base frame and the extension frame and is operable to move the extension frame in an extending direction outwardly from the base frame through the open upper side and a collapsing direction inwardly to the base frame through the open upper side. The transportation rack further includes a compartment unit supported by the extension frame and having a collapsing portion therealong that accommodates the extending and collapsing of the extension frame with respect to the base frame.

BACKGROUND OF THE INVENTION

Assembly of various goods, including various components and subassemblies of goods on an assembly line, requires the availability of the parts to-be assembled at the location of their assembly on the line. In many instances, transportable racks are used to transport parts to an assembly location. These racks can be moved to the location at which the parts are stored and loaded to various compartments, or areas, of the rack, often in manner corresponding to the order of their assembly. The racks are then moved to a specific location on the line where the included parts are needed. Because the parts are often removed from the rack by a human working on the line, the racks are limited in height to what is accessible by the average worker. Further, the number of racks on a line can be limited by the available area adjacent the various stations, as well as the number of racks that can be towed or otherwise transported in a “train” of such racks in one operation. However, such limitations may reduce the number of parts that can be provided to a line at a given time, which may increase the frequency with which racks must be swapped out for refilling. Accordingly, further advances are desired.

SUMMARY OF THE INVENTION

According to an aspect of the disclosure, a transportation rack includes a base frame configured for resting on a surface and including a plurality of first support members arranged in a first prism to define an open upper side and an open front side of the base frame. The transportation rack further includes an extension frame including a plurality of second support members arranged in a second prism and defining an open bottom end and an open front side of the extension frame. The extension frame is slidably received through the open upper side of the base frame. An actuator is coupled between the base frame and the extension frame and is operable to move the extension frame in an extending direction outwardly from the base frame through the open upper side and a collapsing direction inwardly to the base frame through the open upper side. The rack further includes a compartment unit supported by the interior frame and having a collapsible portion therealong that accommodates the extending and collapsing of the extension frame with respect to the base frame.

According to another aspect of the disclosure, a transportation rack includes a base frame configured for resting on a surface and including a lower interior side and an open upper side. The transportation rack further includes an extension frame received through the open upper side of the base frame and defining an upper cross member coupled on an upper end of the extension frame. An actuator is coupled between the lower interior side of the base frame and the upper cross member of the extension frame and is operable to move the extension frame in an extending direction outwardly from the base frame through the open upper side and a collapsing direction inwardly to the base frame through the open upper side. The transportation rack further includes a compartment unit supported by the interior frame and having a collapsible portion therealong that accommodates the extending and collapsing of the extension frame with respect to the base frame. The compartment unit defines a channel therethrough to receive the actuator.

According to another aspect of the disclosure, a method for providing parts to a production line includes transporting an assembly of coupled racks to assembly location. Each of the racks includes a base frame defining an open upper end and an extension frame slidably received through the open upper end of the base frame. The method further includes electrically coupling a first one of the assembly of racks with a control unit and selectively removing parts from a lower section of a compartment unit of the first one of the assembly of racks through an open front side of the base frame. When the parts have been removed from the lower section, the control unit is used to cause an actuator in the first one of the assembly of racks to lower the extension frame through the open upper end of the base frame. A collapsing portion of the compartment unit collapses to accommodate the lowering of the extension frame. The method further includes removing parts from an upper portion of the compartment unit through the open side of the base frame and through an open side of the extension frame.

DETAILED DESCRIPTION

Referring to the embodiment illustrated inFIGS. 1-13, reference numeral10generally designates a transportation rack. The transportation rack10includes a base frame12configured for resting on a surface and including an open upper side14and an open front side16. The transportation rack10further includes an extension frame18defining an open front side20and being slideably received through the open upper side14of the base frame12. An actuator22is coupled between the base frame12and the extension frame18and is operable to move the extension18frame in an extending direction24outwardly from the base frame12through the open upper side14and a collapsing direction26inwardly to the base frame12through the open upper side14. The transportation rack10further includes a compartment unit28supported by the extension frame18and having a collapsing portion30therealong that accommodates the extending and collapsing of the extension frame18with respect to the base frame12.

Referring toFIGS. 1-5, the base frame12is defined by a plurality of mutually rigidly-coupled first support members32and34that extend both vertically (vertical first support members32) and horizontally (horizontal first support members34) to define a first, open-sided prism36(FIG. 8). As shown, the first prism36defined by the first support members32,34is generally considered a rectangular prism that defines a base height38, base width40, and base depth42. In general, the dimensions (height38, width40, and depth42) of the prism36defined by base frame12are configured to maximize an accessible storage area within base frame12, as further described below, while providing for a desired level of mobility of rack10, as also described further below. In particular, the base frame12can be sized to reduce the risk of tipping of base frame12, such as during movement thereof, for example, while providing base frame12with a width40that facilitates movement around a factory floor and a depth42that allows for a reasonable turning radius of rack10, including when multiple racks10are coupled together in the articulating manner discussed below with respect toFIG. 14.

The particular values of the dimensions38,40,42can also vary according to the materials used for construction thereof, including the weight of such materials, as well as the anticipated loading of rack10. In one example, the height38of base frame12can be between about 3 feet and 5 feet. In such an example, the width40can vary from between about 1.5 feet to 3 feet, and the depth42can vary from between about 1.2 feet to 2.5 feet, although the particular dimensions can vary. In the depicted embodiment, the height38is about 52″, the width40is about 36″ and the depth42is about 24″.

As further shown in the figures, and inFIGS. 10 and 11, in particular, the first support members32,34are arranged such that the base frame12is in the shape of the above-described first prism36, while being generally open-sided. In particular, such an arrangement includes the above-mentioned open upper side14and open front side16of the base frame12. As such, the first support members32,34can be of a rigid material and can be rigidly joined together to give base frame12a desired level of support for both extension frame18, as described further below, and for at least partial support for compartment unit28. In particular, first support members32,34can be of a metallic material, including steel or the like, that can be of an appropriate thickness to prevent bending or buckling of base frame12. Further, first support members32,34can be welded together (or otherwise coupled together using alternative means including industrial adhesives, or mechanical fasteners such as screws, bolts (with mating threads integrated with relevant portions of rack10or corresponding nuts), rivets, or the like) at the various intersections thereof to give the desired shape of prism36. It is further noted that while horizontal first support members34can primarily be used to define the open upper side14of base frame12, as well as the opposite bottom52of base frame12(or at least a supportive perimeter thereof), additional horizontal first support members34can be positioned between the open upper side14and bottom side44of base frame12to provide additional structural support for base frame12, including resistance to buckling of vertical first support members32); however, no such horizontal first support members34are positioned across open front side16or upper open side14. Additionally, a plurality of horizontal first support members34may surround a portion of bottom side44. In one example, such support members34may be positioned on the sides of base frame12, with the front side16and the opposite back side being open, as depicted. In another embodiment, an additional horizontal first support member34can be included along bottom side44on the back77of base frame12. Such support members34can be of varying heights, as needed to provide support for base frame12, to help maintain collapsing portion30of compartment unit28within base frame12when extension frame18is in the lowered position, or other such criteria.

In a similar manner, the extension frame18is defined by a plurality of second support members46arranged in the general shape of a second prism48that is of a generally open construction, including along an open bottom end50and the above-mentioned open front side20of the extension frame18. In an embodiment, extension frame18can be lacking a second support member46along an intersection between open bottom end50and open front side20such that extension frame18is continuously open between open bottom end50and open front side20. The prism48defined by extension frame18can be a rectangular prism in the same manner as the prism36defined by base frame12and can be similarly dimensioned but slightly smaller, as described further below, such that extension frame18can slidably fit through the open upper side14of base frame12. As further discussed below, the fit of extension frame18within base frame12, including within open upper side14thereof, can be sufficient for base frame12to support extension frame in the extended position shown inFIGS. 1-3. Additionally, the structure of extension frame18can be sufficient to provide a desired level of support for compartment unit28, under desired loading conditions in both the extended position and the collapsed position (FIGS. 4 and 5). In particular, when in the collapsed position, extension frame18may fully rest on a lower surface54of the bottom52of base frame12such that compartment unit28, including a remaining load thereof, is supported by extension frame18on lower surface54.

As discussed above, base frame12is configured to rest on a surface, which may include the ground, or more specifically, a factory floor or the like. As further discussed, the above-described dimensioning of base frame12can be derived to achieve stability of rack10on such a surface when extension frame18is in both the collapsed position (FIGS. 4 and 5), as well as the extended position (FIGS. 1-3). In some embodiments, however, it may be desirable to add additional supportive elements beneath base frame12to provide a measure of stability on an uneven surface or, as desired, mobility for rack10. As shown in the figures, in the depicted embodiment, such stability and mobility is achieved by coupling wheels56to and extending beneath the bottom52of base frame12. Such wheels56may be rotating caster assemblies in all instances or on one side with the other side being fixed in direction. In various embodiments, wheels56may be coupled to the lower ends of vertical first support members32, along intermediate portions of desired ones of horizontal first support members or on a lower side of surface54(which may be defined by a rigid planar member, such as ⅛″ or ¼″ steel sheet.

In such an embodiment, a brake mechanism58can further be coupled with bottom52of base frame12to selectively prevent movement of rack10by way of wheels. Such a brake mechanism58can include a pedal60that is generally accessible by a user using his or her foot such that pedal60can be depressed to engage or release brake mechanism58. In various embodiments, brake mechanism58can include features to frictionally engage with the surface between wheels56and/or to engage directly with wheels56to prevent rotation thereof.

Turning now toFIGS. 6-9, an embodiment of rack10is shown in which base frame12is constructed with particularly-structured vertical first support members32(i.e. that extend in the direction normal to the open top end) that are L-shaped in respective cross-sections thereof. As can be seen inFIG. 7, in particular, the vertical first support members32include respective generally planar portions62that extend along a longitudinal axis in the direction of height38with a material thickness of, for example, between 3/32″ and ¼″ (although other thicknesses are contemplated, depending on the use and application of rack10). Planar portions62can be integrally-formed together (such as in a single L-shaped extrusion) or rigidly affixed together (such as by welding or the like) at a 90° angle to form the desired L-shaped cross section. Further, the horizontal first support members34can be single planar members of a desired thickness to provide the above-described supportive characteristics thereof. Accordingly, the difference in the dimension of the overall height38, width40, and depth42of base frame12and the corresponding dimensions of the interior66(FIG. 7) of base frame12can vary only by the chosen material thickness of first support members32,34. Such construction allows the similarly-corresponding dimensions of extension frame18to be as close as possible to those of base frame12. In one embodiment, the dimensions of extension frame18can be determined by subtracting the material thickness of base frame12and a reasonable tolerance (e.g., 1/16″ to ⅛″) from the dimensions (height38, width40, and depth42) of base frame12.

As further shown inFIGS. 6 and 7, the vertical first support members32, constructed as described above, can receive the corresponding vertically-oriented ones of second support members46within the respective portions of interior66of base frame12such that the vertical edges64of extension frame18are supported the L-shaped cross-sections of the vertical first support members32. In this arrangement, the planar portions62of the vertical first support members32can, thusly, overlap the second support members46of extension frame18, which can maximize the area within rack10that can be occupied by compartment unit28, as described further below, and can, further, maximize the area of both the open front side16of base frame12and the open front side20of extension frame18, thereby maximizing the area through which compartment unit28can be accessed by a user through base frame12and/or extension frame18. In a further embodiment depicted inFIGS. 15 and 16, vertical support members236of base frame212can include an additional interior planar member312such that the vertical support members236define U-shaped cross sections that can receive the corresponding support members246of extension frame218therein. In such an embodiment, the U-shaped cross sections of vertical support members232may provide additional support for extension frame218, particularly when in the raised position shown inFIG. 15. It is noted that the operation, use, and possible variations are generally the same as those discussed elsewhere with respect to rack10, shown inFIGS. 1-14. Further, any additional features not specifically described herein with respect to rack210, shown inFIGS. 15 and 16, are generally the same as those described elsewhere. In a further variation, both base frame12and extension frame18can be constructed of tubular members with extension frame18sized to fit within base frame12, accordingly.

Returning toFIGS. 6 and 7, in the depicted embodiment, the second support members46can define generally tubular cross sections, such as the depicted rectangular cross sections, which may be hollow, to provide an increased resistance to bending and reduced weight. Further, such construction can allow for a smaller or more narrow cross-section than possible by way of the flat and L-shaped cross-sections of the first support members32,34, which facilitates the above-described overlapping arrangement of second support members46with first support members32,34.

Returning now toFIGS. 1-6, the compartment unit28is described in greater detail. In particular, compartment unit28includes an arrangement of flexible fabric columns68. The columns28can be defined by lengths of fabric folded into U-shaped sections. In particular, the fabric can be a polymer-coated textile sheet, including vinyl fabric or the like. In this manner, the fabric lengths can define facing sections72thereof extending through the height of compartment unit28. In particular, a number of such folded fabric sections72can be included to correspond with a desired number of columns68, including four, for example, as depicted in the figures, although more or fewer columns68can be included, as desired depending on the needs of the user and the construction of rack10, as described herein. The columns68can be affixed together or separately assembled with extension frame18, as discussed below. The columns68can further include a plurality of horizontal members70coupled therein between the facing fabric sections72such that horizontal members70can maintain the fabric sections72in the depicted facing arrangement within the overall U-shaped configuration described above. Further, the horizontal members70can define a corresponding plurality of compartments74within columns68and within compartment unit28, overall. The compartments74can be used to retain and transport various parts P (FIGS. 10 and 11) or components via rack10to a desired assembly area, for example. In this manner, horizontal members70can be generally rigid so as to support the weight of various items thereon without causing deformation of the columns68. In an embodiment, horizontal members70can include cardboard, wood, or plastic sheets covered with fabric, such as nylon, vinyl fabric or the like, which can be sewn to the facing fabric sections70(along with an intermediate rear section extending between the facing fabric sections70). The horizontal members70can be spaced at regular or varying intervals along columns68to achieve the desired configuration of compartments74. In this manner, a plurality of flexible side walls76of each compartment74are defined by the sections72of fabric between the horizontal members70. In a variation of the depicted embodiment, the columns68may be approximately half of the depicted dimension along the depth42of rack10. Such columns68may be adjacent to and accessible through open first side16of base frame12in a manner similar to those depicted inFIGS. 1-6. In this manner, additional half-depth columns may be included in compartment unit28adjacent to and accessible through open second side77of base frame12opposite open first side16. Such a configuration can allow a single rack10to provide parts or the like to different adjacent stations in an assembly line.

As shown inFIGS. 4 and 5, the flexible nature of compartment unit28in the extending24and collapsing directions26, by way of the above-described fabric construction of columns68, accommodates the extending and collapsing of the extension18frame with respect to the base frame12. In particular, as can be seen with additional reference toFIGS. 8 and 9, movement of extension frame18with respect to base frame12by operation of actuator22(described further below) moves extension frame18in its entirety with respect to base12and, in particular, through the open upper side14of base frame12such that, when extended, the bottom end50of extension frame18is spaced apart from the lower interior side44of base frame12by an extension distance D that also corresponds to the distance by which extension frame18extends outward from open upper side14of base frame12. In such a condition, compartment unit28, which is supported by rack10by being coupled with extension frame18adjacent the upper end78thereof, extends downwardly through the height of extension frame18and out of the open bottom end50thereof to a position in contact with or adjacent (e.g., within about 3″) of lower interior side44of base frame12. In this manner, the absence of a second support member46between open bottom end50and the open front side20of extension frame18removes a potential obstruction of any compartments74that align with the open bottom end50of extension frame18.

As shown inFIG. 5, when actuator22operably lowers extension frame18in the collapsing direction26, the open bottom end50of extension frame18moves toward and into contact with, or at least adjacent to, lower interior side44of base frame12, thus closing the gap present therebetween in the extended condition. During such movement, the flexible side walls76of the compartments74located between the open bottom end50of extension frame18and the lower interior side44of base frame12, which roughly defines the above-mentions collapsing portion30of compartment unit28, can bend or fold to allow the compartments74in the collapsing portion30to collapse by the adjacent horizontal members70moving closer together, thereby shortening the height of compartment unit28to the retracted length of rack10, which closely corresponds with the height38of base frame12. Such collapsing can occur due to the weight of the remaining portion of compartment unit28above the collapsing portion30against the lower interior side44of base frame12, which can be furthered by the compartments74in the remaining portion being occupied by parts P and, accordingly, bearing weight against the compartments74in collapsing portion30.

As can be seen inFIG. 11, for example, the compressed compartments74within the collapsing portion30still occupy some vertical space within rack10when extension frame18is in the collapsed position. In one example, such space may be approximately equal to that of one non-collapsed compartment74. Accordingly, the number of compartments74in the vertical direction, as well as the distance D that extension frame18travels may be configured to accommodate this space within extension frame18. It is noted that in the present embodiment, the entire compartment unit28can be generally uniform in construction in the extending24and collapsing26directions such that the entire compartment unit28can be capable of collapsing (which can provide for easy shipping and storage of compartment unit28). In this embodiment, the portion considered the collapsing portion30is, as described above, the portion that extends between the open bottom end50of extension frame18and the lower interior side44of base frame12when extension frame18is in the extended position. Accordingly, when lowering extension frame18, some degree of collapsing of compartments74outside of the collapsing portion30may occur during lowering of extension frame, particular when such compartments74are unoccupied.

In a further variation of the depicted embodiment, rack10may include separate upper and lower portions of compartment unit28with the lower portion of compartment unit corresponding with the illustrated collapsing portion30and the upper portion including the remaining portion thereof. In such a variation, the lower portion may be made of additional columns68affixed on bottom end50of extension frame18, such as by including additional support members46in the direction of the width of rack10. In this manner, the columns68of the lower portion of compartment unit28can be mounted to bottom end50in a manner similar to that shown inFIG. 7. In such a configuration, the columns68in the upper portion can be shorter versions of the depicted fabric columns68or could include rigid bodies of plastic, metal or the like (with a channel therein to accommodate actuator22). The lower columns68can, similarly, be shorter variations of the columns68depicted herein. In a still further variation, rack10can be used without compartment unit28or with only an upper portion of the compartment unit28, as described above. In such a variation, items can be stacked or otherwise placed on surface54of base frame12when the extension frame18is in the raised position. Once such items have been removed, extension frame18can be lowered for access to items stored therein (such as by being included within a shortened compartment unit28or on a shelf or other surface extending over bottom end50of extension frame18).

In the illustrated embodiment, the compartment unit28may be comprised of a number of individual columns68, as described above, that may be independently mounted to extension frame18. In particular, each such column68may include a pair of open loops82on the uppermost portion thereof (FIG. 7) that extend in the direction of the depth42of base frame12. A corresponding pair of mounting rails80may extend through the loops82and couple with opposite second support members46that define a top end78of extension frame18. The mounting rails80may fit into slots in such second support members46that are open only on the upper side thereof to allow the rails80to drop into the slots and to be retained therein by the weight of the associated column68. In other arrangements, mounting rails80may screw or bolt into the associated second support members46. In other embodiments, the columns68may be coupled together in an integral compartment unit28such that the entire compartment unit28is assembled to and disassembled from extension frame18in a single assembly.

With reference toFIGS. 8-11, the actuator22is described in greater detail. In particular, the actuator22may be a linear actuator having a piston84extendable from a housing86. In the present embodiment, the piston84may be driven by an internal power screw arrangement (both housing86and piston84being hollow to accommodate the screw portion with at least a portion of the interior of piston84being threaded such that rotation of the screw drives linear motion of the piston84in the extending24or collapsing direction26, depending on the direction of rotation. In turn, the actuator22may include an electric motor88to drive rotation of the screw (either directly or by a reduction mechanism therebetween). To achieve the desired travel of extension frame18, the actuator22is configured such that piston84has an extendable length equal to distance D. In other embodiments, actuator22may be a hydraulic or pneumatic actuator with appropriate assemblies for driving linear movement of such actuators being mounted beneath surface54of base frame12.

As shown inFIG. 10the actuator22can be mounted to base frame12along a central portion90of the substrate defining lower surface54of base frame12. In this manner, housing86may be positioned beneath surface54to avoid interference with compartment unit28. Opposite from the mounting with base frame12, actuator22couples with extension frame18by way of an extension arm92that couples on one end thereof with the free end of piston84and on the other end thereof with an upper cross member94of extension frame18. The extension arm92essentially occupies the vertical distance between actuator22and the top end78of extension frame18, as actuator22has a height of approximately the extension distance D. As further shown, cross member94can generally bisect extension frame18along the width of rack11and can have extension arm92coupled therewith at the midpoint thereof such that actuator22may be centrally positioned with respect to both extension frame18and base frame12. This configuration provides for balancing of extension frame18by actuator22and extension arm92during lifting of extension fame18and when maintaining extension frame18in the elevated position. As further shown, cross member94may be spaced above the top end78of extension frame18by a pair of upper frame members96that extend vertically above the second support members46to which compartment unit28is mounted. Such construction allows for access to mounting rails80during assembly and disassembly thereof with extension frame18and, further, provides for additional height of rack10to accommodate the coupling of extension arm92with piston84and with cross member94.

To accommodate the central positioning of actuator22, compartment unit28may define a channel98therein that corresponds with the location of actuator22. As shown inFIG. 11, the channel98of the depicted embodiment can be a gap present between adjacent columns68by way of the separate construction and mounting of the adjacent columns68, although other arrangements are contemplated. In such an embodiment, the overall number of columns68is even such that one of the channels98between the successive columns68aligns with actuator22. In a variation where an odd number of columns68is desired, actuator22can be offset from the center of lower surface54to align with one of the channels98between such columns68. Additional actuators22can be included in such a rack10in additional channels98to balance the force applied to extension frame18and/or to provide additional lifting force therefore. Such additional actuators22can be included in further variations of rack10with an increased width40, regardless of whether an even or odd number of columns68are present, to provide additional force distribution and/or lifting force for larger variations of rack10that what is presently depicted.

As further shown inFIG. 10, rack10can include an electrical coupling100mounted externally on the base frame12(such as by being fixedly coupled on one of the first support members32,34. Electrical coupling100is, in turn, electrically connected with the electric motor88of the actuator22. In this manner, an external control unit104can be connected to actuator22by way of coupling100for providing directional control of motor88to operate actuator22. Such an assembly allows the control unit104, which may be somewhat bulky, to be positioned in a location (e.g., a station on an assembly line) where one or more racks10may be used, including in groups, as discussed further below. In such an arrangement, the control unit104may be connected with a particular one of such racks10for which movement of extension frame18is desired. Because such movement may occur generally infrequently and may be coordinated with the need to move additional extension frames18of other racks10, a cost and/or weight saving may be realized by associating control units104with stations, rather than individual racks10. In this manner, control unit104can be decoupled from electrical coupling100and reconnected with the coupling100of another rack10, when needed. Such use can also allow control unit104to be coupled with other safety interlock devices, such as foot pedals, or the like, to require a user to be safely positioned away from rack10prior to movement of extension portion18. Alternatively, coupling100may be replaced by a control unit104directly mounted to rack10and directly coupled with motor88.

As shown inFIGS. 9 and 10, the base frame12may further include a coupling extension106mounted on one side thereof and a hitch member108mounted on a side opposite the side to which coupling extension106is mounted. The coupling extension106and hitch member108can be configured for mutual engagement such that, as shown inFIG. 14, adjacent racks10a,10bcan be coupled together by attachment of the coupling extension106aof one rack10awith the hitch member108bof another rack10b. As illustrated, hitch member108can be a generally straight post mounted in a downwardly-extending manner beneath one of the horizontal first support members34defining the bottom52of base frame12. In such an arrangement, coupling extension106can include a looped portion110on a free end thereof through which the hitch member108can be received. Further, the coupling extension106can be spring-biased toward the retracted position shown inFIG. 10to provide automatic retraction thereof when decoupled from hitch member108. Further, in such an arrangement, the biasing of coupling extension106can maintain loop110in an engaged position with hitch member108due to the downward orientation thereof, which is such that the biasing of coupling extension106is maintained against the horizontal first support member34from which hitch member108extends. Other variations of both hitch member108and coupling extension106are possible, including an arrangement where hitch member108extends upward relative to lower end52of base frame12with coupling member being biased downwardly or being unbiased such that gravity maintains engagement with hitch member108. Further, hitch member108may be hooked or arced, may be a ball, or may be otherwise shaped according to known variations in such elements, with coupling member being configured for engagement therewith. Base frame12may further have a handle112coupled therewith to allow for manual movement of rack10.

The coupling of multiple racks10aand10btogether, as described (which can also achieve coupling of racks10band10c) can allow multiple racks10to be configured with the respective extension frames18in the elevated position and loaded with parts P in a single location (e.g., a warehouse or the like). Such parts P can be those needed at a particular station or adjacent stations in part of a line for designated portion of assembly of a product or a series of products, components, subassemblies, or the like (such as an automotive component, for example), allowing the assembled racks10a,10b,10cto be towed, manually by an individual or using a designated vehicle, to the location where the parts P are needed. Once appropriately located, the parts P from the accessible portions of racks10a,10b,10ccan be unloaded from the compartments74during assembly in that particular area. The accessible portions of the racks10a,10b,10ccan be the compartments74located within the open front side16of base frame12, for example. When the compartments within either the collapsing portion30aof the accessible area (e.g., open front side16a) of a first rack10aare empty, the rack10acan be coupled with the control unit104of the associated assembly area for lowering of the extension frame18a, thereby giving access to the previously inaccessible compartments74. In this manner, the parts P within the racks10acan be removed successively, first within the accessible area of the collapsing portion30a, then within the remaining compartments74aafter lowering of the extension portion18a. Once the first rack10ais empty, the parts P in the next rack10bcan be removed in a similar manner, followed by the parts P in rack10c. In various embodiments, three or more racks10can be coupled together and towed to an assembly location. In some embodiments, up to five racks10can be coupled together and towed (although more than five racks10can coupled and towed in some configurations). In such an embodiment, in the depicted configuration of compartments74, the addition of the collapsing portion30to compartment units28can allow for the addition of sixteen compartments74per rack10, which is an increase of over 40% from a comparable non-extendable rack. When coupling five racks10together, an extra eighty compartments74can be included in a single “train” of racks10, which can reduce the frequency with which racks10need to be swapped out for reloading.

In this manner, a method for providing parts P to a production line (including a portion thereof) can include transporting an assembly of coupled racks10, as discussed above and shown inFIG. 14, to the assembly location. Various ones of the parts P can then be selectively removed from a lower section, either collapsing portion30aor the entirety of open front side16aof base12a, of the compartment unit28aof the first of the assembly of racks10athrough an open front side16aof the base frame12a. When the parts P have been removed from the lower section (collapsing portion30aor the entirety of open front side16a), the control unit104can be used to cause the actuator22ain the first rack10ato lower the extension frame18athrough the open upper side14aof the base frame12a. In this manner, the control unit104can be coupled with the electrical coupling100aof rack10abefore or after unloading of the lower area thereof. As discussed above, the collapsing portion30aof the compartment unit28acollapses to accommodate the lowering of the extension frame18a. Subsequently, parts are removed from the upper portion112aof the compartment unit28athrough the open front side16aof the base frame12aand through the open front side20aof the extension frame18a. Subsequently, parts P can be removed from successive racks (e.g., racks10band10c) in a similar sequence with control unit104being decoupled from an empty rack (e.g., rack10a) and coupled with the next rack (e.g., rack10b). As discussed above, such as sequence can include up to 5 racks10or more coupled together and transported to the assembly line or portion thereof.