APARATO PARA MEDIR LA HUMEDAD DEL SUELO Y PARA DESENCADENAR UN PROCESO DEPENDIENTE DE LA HUMEDAD

摘要

A device for measuring ground humidity and triggering an operation dependent on humidity contains in a housing an expansion member (35) which changes its length with change in humidity. The expansion member (35) acts on a displaceable slide (41), which is provided with a geared rack (54). The geared rack (54) meshes with a toothed ring (53) of a display element (17) which has a contact element (71). A change in length of the expansion member (35) causes turning of the display element (17) and closure of a contact given a specific variable angular position.