Patent ID: 6498468
Filing Date: 2002-12-24
Classification: G05F

Abstract:
Circuit arrangement for the supply of an electrical coil (L) of a solenoid valve with a predetermined operating current from a voltage source with differing operating voltages (Ub), the coil being arranged in series with a first controllable circuit element (T2) and a current sensor (R) having a measuring signal (IÃ—R), and the measuring signal of the current sensor being compared with a reference value (Uref) through a first comparator (1), and a timed switch (2) being triggered by an output signal (A) of the comparator when the measuring signal (IÃ—R) exceeds said reference value (Uref), the first circuit element (T2), activated by an operating signal, being disconnected by the output signal of the timed switch (2), until the measuring signal (IÃ—R) exceeds the reference value again (Uref), and in which through a second comparator (4) the measuring signal of the current sensor (R) is compared with a signal (Uc) that is steadily increasing independently of a change of the operating voltage (Ub), said signal also being triggered through the operating signal (M), and the timed switch (2) is triggered by an output signal (B) of the second comparator (4), when the measuring signal (IÃ—R) exceeds the steadily increasing signal (Uc), before the measuring signal (IÃ—R) exceeds the reference value (Uref).