A double pump adapted for use as an artificial heart includes two ventricle-simulating chambers that are provided with respective inlets and outlets having valves incorporated therein and that are separated by a common partitioning wall structure. The wall structure has sections that are driven away from each other to reduce the volumes of respective ventricle chambers and expel liquid from the chambers through the outlets. The wall structure can also move laterally in response to differences in pressure between the chambers and hence change the volumetric ratio between them. This ensures a balanced action between the two halves of the heart-simulating pump during a systole phase and a diastole phase. The link mechanism is actuated by a cord through a motor, although only in one direction in the pressure phase, and hence the aforementioned changed volumes are readjusted primarily through the pressure exerted by the inflowing fluid. |