Diagnostic method for poppet valves and measuring device for carrying out said method

摘要

The invention relates to diagnostic methods according to the preamble of the equivalent claims 1 and 2, with which the state of a poppet valve in the course of the switching cycles and/or events thereof, such as the occurrence of pressure shocks or surges during continuous operation is/are monitored continuously, the measured signals are stored and the stored measured signals are interpreted in a targeted manner and early indication of cases of damage is carried out. According to a preferred variant of the diagnostic method, said aim is achieved in that at the same time as the force-time curve of the actuating force or the reaction force (F1(t); F2(t)), a displacement-time curve (h(t)) of the displacement (h) of the at least one closing element (8*) is measured, in that the force-time curve of the actuating force or of the reaction force (F1(t); F2(t)) and the displacement-time curve (h(t)) are combined with each other and used to determine a force-displacement curve of the actuating force or the reaction force (F1(h); F2(h)), in that the current force-displacement curve of the actuating force (F1(h)) or the reaction force (F2(h)) of a switching cycle, in each case determined over the operating period or lifetime of the poppet valve (100), is compared with an earlier, stored curve, in that deviations are determined from the comparison, in that, within a predefined tolerance range for said deviations, the latter are accepted, and in that, when said deviations exceed the predefined tolerance range, a message and/or a control signal is/are generated.

主权项

1. A diagnostic method for poppet valves with which an actuating force (F1) representing an action force that is generated by a fluid-actuated spring piston drive (2) of the poppet valve (100) is determined for at least one closing element (8*) of the poppet valve (100) in the form of a force-time curve, the actuating force (F1) is either determined directly or from a reaction force (F2) resulting from the actuating force (F1) in the poppet valve (100), wherein the actuating force (F1) or the reaction force (F2) is determined by measuring expanding deformations caused therefrom, and the measured, current force-time curve of the actuating force (F1(t)) or of the reaction force (F2(t)) is saved and subjected to an evaluation, characterized in that
a displacement-time curve (h(t)) of the displacement (h) of the at least one closing element (8*) is measured at the same time as the force-time curve of the actuating force or of the reaction force (F1(t); F2(t)), and the force-time curve of the actuating force or of the reaction force (F1(t); F2(t)) and the displacement-time curve (h(t)) are combined with each other, and a force-displacement curve of the actuating force or of the reaction force (F1(h); F2(h)) is determined therefrom, the current force-displacement curve determined during the operation or life of the poppet valve (100) of the actuating force (F1(h)) or of the reaction force (F2(h)) of a switching cycle is compared with an earlier stored force displacement curve of the actuating force F1 (h) or of the reaction force F2 (h) of an associated switching cycle, deviations are determined from the comparison of the actual switching cycle with the earlier switching cycle, wherein either deviation are determined to be within a predetermined tolerance range, and are accepted; or in the alternative, the deviations are determine to exceed the predetermined tolerance range, and a message and/or control signal is/are generated, the displacement (h) is determined by an indirectly representative physical quantity within the poppet valve (100), and expanding deformations caused by the generation of the displacement (h) in the drive (2) is used as a physical quantity.