In  another  embodiment,  an  adjustable  roller conveyor

65 module includes first and second support structures. Each of the first and second support structures has first and second laterally spaced, elongated frame members arranged in par-

a11e1 and extending along a central longitudinal axis. Extend- ing between, and supported by, the parallel frame members is a plurality of rollers, each of which rollers rotates about an axis which, in a typical embodiment, is perpendicular to the central longitudinal axis and parallel to the axes of other rollers among the plurality. A typical embodiment is further characterized in that the roller axes of the rollers supported by each support structure lie along a roller plane and are spaced equally in accordance with a predetermined roller- axis spacing.

In various embodiments, the roller axes of the rollers supported by the first support structure are coplanar with the roller axes of the rollers supported by the second support structure. Accordingly, in a typical embodiment, one of the first and second support structures is reciprocably received between the elongated frame members of the other of the first and second support structures such that one support structure is regarded as an outer support structure and the other support structure is regarded as an inner support structure. Moreover, to accommodate the linear retraction of the inner support structure into (e.g., between the first and second frame members of) the outer support structure, each roller of a selected set of rollers of the outer support structure is selectively removable. With the removal of each succes- sive roller in the outer support structure, the inner support structure is permitted to linearly retract into the outer support structure by a distant corresponding to the fixed spacing between the rollers of the outer support structure. Conversely, as the inner support structure is extended, rollers may be added to the outer support structure to eliminate “gaps” in roller-spacing continuity.

In some versions, the elongated frame members of the outer and inner support structures include roller-mounting apertures, each of which apertures is adapted for receiving an end a roller axle. The roller-mounting apertures are equally spaced in accordance with a predetermined roller- axis spacing. The roller-mounting apertures are furthermore situated so that the elongated frame members of the inner support structure are slidable into incremental positions in which roller-mounting apertures of the inner support struc- ture are aligned with roller-mounting apertures of the outer support structure in an overlapping relationship. In a typical version, the axles of rollers mounted in overlapping aper- tures extend through the opposed roller-mounting apertures of the inner support structure and at least partially into the opposed roller-mounting apertures of the outer support structure. Rollers mounted within the roller-mounting aper- tures of both the inner and outer support structures are regarded as members of a more broadly definable set of rollers referred to as “shared” rollers. It will be appreciated that the number of shared rollers depends in various imple- mentations on the degree of extension of the inner support structure with respect to the outer support  structure.

In various aspects, the outer support structure includes extension apparatus capable of extending beyond the “free end” of the outer support structure opposite the end beyond which the inner support structure extends for adjusting the overall length of the conveyor module. Various versions further include extension apparatus for similarly extending beyond the free end of the inner support structure. The capacity for the extension apparatus in any particular version to extend “beyond the ‘free end”’ of the support structure in no way implies that, in such a version, the extension apparatus must be retractable into a position in which it does not extend beyond the free end to some degree. For instance, in a version illustrative of the preceding point, the “most retracted”  position  of  the  extension  apparatus  is  one  in which the extension apparatus still protrudes beyond the free end; however, even in this version, the extension apparatus is capable of “extending beyond the free end” of the support structure, albeit to some greater degree than when it is in its 5 most retracted position. The same non-limiting interpreta- tion applies equally to single-support-structure conveyor modules that include extension apparatus.