Washing head in automatic immunological assay apparatus

Automatic apparatus for immunological assay of at least one substance in a plurality of samples to be analyzed, the apparatus comprising a rotary module for supporting samples, a rotary module for supporting a plurality of reaction vessels, a rotary module for supporting reagents, at least one of which is in the form of magnetic particles, means for driving the rotary modules stepwise in a rotation direction, means enabling desired quantities of samples and of reagents to be conveyed into the reaction vessels, magnetic particles washing means comprising a washing head associated with the rotary module for the reaction vessels and a plurality of injection and suction needles for injecting a washing liquid for said magnetic particles into said vessels and for sucking up the washing liquid, and vessel cleaning means associated with the rotary module for the reaction vessels said vessel cleaning means comprising at least some of the same injection and suction needles used by said magnetic particles washing means and an additional group of injection and suction needles for injecting a vessel-cleaning liquid into the vessels and for sucking up the cleaning liquid from the vessels, said additional group being mounted on said washing head adjacent to said injection and suction needles of the magnetic particles washing means.