Pump for flowable, in particular pasty matérials, in particular for a medical laboratory

A pump for conveying flowable paste-like materials, including a conveyer line which has a plurality of conveyer elements sequentially arranged in the longitudinal direction of the conveyer line to selectively displace and release at least a part of the volume of material conveyed by the conveyer line. The pump possesses a working chamber consisting of an annular chamber externally bounded by a housing of the pump and interiorly by a cylinder. The conveyer elements incorporate bellows elements each in the form of a ring of an elastically extensible material acted upon by a pressure medium at a side opposite the material being conveyed, with the bellows elements being formed by a common hose-like bellows which is retained on an inner wall of the housing. A support ring is located between respectively each of the bellows elements for retaining the bellows on the inner wall, with pressure lines located between the support rings and passing through the housing to open into the annular chamber. A control device causes a pressure source and a vacuum source to be alternatively connectable with the pressure lines, with the housing being closed by two end walls in each of which there is selectively provided at least one of an input and output opening.