Abstract: The invention relates to a metering pump for liquid and gaseous media, which is provided with a deformable tube for the medium to be conveyed. The pump casing accommodates a rotating member which squeezes the tube against an inside surface in the pump casing. The tube is guided around the rotating member constituting a main eccentric, through a looping angle of 360.degree.. A secondary eccentric, the diameter of which is smaller than the diameter of the main eccentric, is mounted on the shaft of the main eccentric. The main eccentric is a ball bearing, the outer race of which clings to the tube by surface adhesion during rotation of the shaft. The ball bearing is rotated with the rotating shaft, while the outer race performs a radial reciprocating motion, thus avoiding any flexing of the tube, which is merely cyclically compressed and released again.

Abstract: A volume pump which comprises a cylindrical pump chamber including therein a plurality of compartments which are radially formed with flexible partitions and side plates adapted to close opposite open sides of the pump chamber, suction and delivery means arranged in relation to the pump chamber and a deflection means disposed at a center of the pump chamber to successively compress each compartment.

Abstract: A membrane pump comprising a housing having an inner cylindrical surface, an annular member in the housing and having an outer surface defining with the inner surface of the housing a working space. A hollow rolling piston is arranged in the interior of said annular membrane. An eccentric drive including an arm fixed at one end to a drive shaft carries at its other end a roller engaging the inner surface of the rolling piston for rotating the latter about its axis while pressing the outer surface thereof against the inner surface of the membrane, whereby the outer surface of the membrane is pressed at a revolving sealing region against the inner surface of the housing.

Abstract: A volume pump which comprises a cylindrical pump chamber including therein a plurality of compartments which are radially formed with flexible partitions and side plates adapted to close opposite open sides of the pump chamber, suction and delivery means arranged in relation to the pump chamber and a deflection means disposed at a center of the pump chamber to successively compress each compartment.

Abstract: A fluid pressure motor having a plurality of independent, freely distortable pressure chambers connected together in the form of a multi-lobed rosette shaped structure arranged between two rotatable supporting plates inclined at an angle to each other. The chambers are elastically deformable by the fluid pressure and there are at least two rosette shaped structures superimposed between the rotating support plates with adjacent chambers in each of the rosettes being in fluid communication with each other and with a control system for introducing a fluid pressure medium into the chambers sequentially and expelling it after the chambers have attained maximum volume.

Abstract: The rotation of a helix within a deformable tube which is located within and attached by the ends to a pump casing of circular cross section causes fluid to flow between the tube and pump casing when the tube contains at least one longitudinal rib continuously connected to the pump casing. Changes in the cross sectional area of the pump casing and changes in the configuration of the helix permits additional fluid to be drawn into the fluid stream or a portion of such fluid to be discharged from the space between the deformable tube and the pump casing at the transitions in cross sectional areas of the pump casing or changes in configuration of the helix.