device for automatic bacteriological analysis policy implementation

摘要

1372847 Automated bacteriological sampling UNILEVER Ltd 27 Oct 1971 [29 Oct 1970] 51377/70 Heading C6F [Also in Division B1] In the automated filling of Petri dishes with bacteriological components, dishes from eight stacks of twenty dishes 2, Fig. 1, are taken on carrier arms 3 through stations II to receive the inoculation and a diluent, III for the addition of nutrient agar and IV for labelling, after which they are added to a stack of similarly prepared dishes (not shown). At stations II and III the dish 2 and its sub-carrier 11, Fig. 4, are rotated by a rubber driving wheel 12 whereby the contents of the dish are properly mixed together. When arm 8 moves downwardly to the inclined position shown, a second arm and cam cause the Petri dish lid to move back horizontally. In addition to ordinary delivery systems 15, a pipette dispensing system 13 transfers an inoculation sample from a pot 14 into a first dish containing diluent and thereafter transfers diluted inoculation samples sequentially from the first dish to the second, from the second dish to the third and so on (serial dilution technique). The pipette, which forms the subjectmatter of Specification No. 1372848, may consist of an extruded tube of wax or agar of clover leaf cross-section. The used portion of the tube is cut off after each transference and a further portion extruded. Alternatively, a continuous length of tubular material may be supplied from a reel.