MEASURING SYSTEM FOR THE CONTROL OF RESIDUAL DUST IN SAFETY VACUUM CLEANERS

摘要

The invention relates to a measuring system (10) for the control of residual dust in safety vacuum cleaners. The inventive system comprises at least one grid-shaped measuring electrode (11) downstream of and behind the filter component (4). Said measuring electrode (11) is electrically insulated towards the safety vacuum cleaner and covers the entire cross-section of flow. Said measuring electrode (11) transmits a current which is produced by a contact voltage between the measuring electrode and the particles to a unit (12) analyzing said measuring value depending on the particle concentration. The measuring electrode (11) may be arranged downstream of and behind the filter (4) or behind the turbine (5) or downstream of and behind the filter (4) but in front of the turbine (5). Said turbine (5) and/or the housing (1) is directly grounded or artificially grounded in order to discharge the particles before the actual registration. The measuring current is amplified by a differential amplifier (12) and is transmitted to a unit processing the measured value, thereby prompting an optical and/or acoustic alarm and/or the disconnection of the turbine (5) and/or the automatic replacement of the filter (4) and/or the turbine (5) together with the filter (4). The progression of the measuring circuit can be saved for a statistical evaluation of the measured data and can be transmitted to an external data processing system or to a computer via an interface. The desired values and the other parameters of the appliance can be influenced by means of said external data processing system on the basis of the transmitted measured data.