Process and device for automatically detecting the response voltage of an electromagnetic component, in particular an electrovalve

Process for automatically detecting the response voltage of an electromagnetic valve having a coil connected in series with a measuring resistor, comprising the steps of

• applying an increasing testing voltage across the series connection of the measuring resistor and the coil of the electromagnetic valve;
• measuring the change of the voltage drop across the coil of the electromagnetic valve and indicating the instantaneous measured voltage value;
• differentiating the voltage drop across the measuring resistor to produce a switching signal when current flowing through the series connection decreases due to the response of the electromagnetic valve;
• stopping by means of the switching signal the indication of the instantaneous measured voltage value;
• the increasing testing voltage being a staircase-shaped voltage produced by controlling a digital-to-analog converter by a free-running binary counter;
• and
• the switching signal being a pulse produced during the response of the electromagnetic valve and being applied to a second counter to stop the indication of the instantaneous measured voltage independently of the output of the digital-to-analog converter.

Device for automatically detecting the response voltage of an electromagnetic valve having a coil connected in series with a measuring resistor, comprising

• means for applying an increasing testing voltage across the series connection of the measuring resistor and the coil of the electromagnetic valve;
• means for measuring the change of the voltage drop across the coil of the electromagnetic valve and indicating the instantaneous measured voltage value;
• means for differentiating the voltage drop across the measuring resistor to produce a switching signal when current flowing through the series connection decreases due to the response to the electromagnetic valve;
• means for stopping by means of the switching signal the indication of the instantaneous measured voltage value;
• the measuring means including an indicating device which is designed in such a way that it indicates and fixed the indication of a voltage value applied thereto;
• and
• the stopping means including a switching device for connecting the instantaneous measured voltage to the indicating device and disconnecting the same at the instant at which the electromagnetic valve (6) responds.