Rack for diagnostic diffusion plates

Claim 1

In a disposable rigid plastic rack for receiving a plurality of diagnostic diffusion plates, each having external longitudinal flanges, said rack comprising: a. a substantially planar elongate rectangular base presenting side and end edges; b. a plurality of four elongate rectangular openigns of substantially equal dimensions arranged in side-by-side relationship in said base, each of said openings having elongate side edges substantially parallel to the end edges of said base and end edges substantially parallel to the elongate side edges of said base; c. end walls integral with and upstanding from the end edges of said base; d. a side wall integral with said base a side edge thereof and including interrupted portions upstanding from said base; e. an integral and upstanding plate positioning block on said base substantially midway the side edge of each opening and spaced from a side edge of each said opening, said blocks having inner edges spaced from said base a distance substantially corresponding to the thickness of a plate flange; each said block adjacent each opening cooperating with said base to define a compartment adapted to receive one of the plates, each of said compartments having an entry for a plate at the side remote from said side wall; f. integral rib upstanding from said base and which includes one of said plate positioning blocks between the side edges of two adjacent said compartments one of said adjacent compartments being an end compartment; said rib being substantially parallel to the side edges of said compartments and extending substantially the full length of said side edges; said rib cooperating with said plate positioning blocks to receive two of said plates in side-by-side relationship transverse to the side edges of said compartments; g. reinforcing ribs depending from the underside of said base along portions of the periphery and between the side edges of said compartments which do not have said upstanding rib; and h. a plurality of pairs of relatively short substantially equally spaced apart ribs depending from teh underside of said base, at least one pair of said ribs being positioned at each of two opposite corners of each said compartments, each of said pair of ribs forming a channel substantially parallel to the side edges of said compartments, and each channel being in alignment with a channel formed by another pair of said ribs at said opposite corner of said compartment whereby the rack by means of these depending ribs is adapted to engage a shaft mechanism on a cooperating diagnostic plate viewer.