System for determining surface tension in a solution, especially a washing or surfactant solution, using the bubble pressure method, whereby a more linear pressure gradient is obtained by repositioning the pump and adding a choke

摘要

System for determining the surface tension of a solution contained in a container, especially a surfactant solution (1) or suds of a washing machine. The system uses the bubble pressure method as described in DE10022863.1. To improve the method the pump for generation of a volume flow is arranged in the bypass (9) and an additional choke (13) is arranged in the in the pressure measurement chamber (5) between the capillary (4) or pressure sensor (6) and the pump (3).