| 摘要 |
An electronic control device for bistable type solenoid valve is described, particularly for watering systems, that comprises a power supply battery (B) and a logic control unit (M) to transfer electric power from the battery (B) to the solenoid valve (XL). The device provides a protection against the condition of exhausted battery that is based on the presence of a condenser (C) set in parallel to the battery (B) and a switch (S) having first switching means (P1) interposed between the battery (B) and the condenser (C) and second switching means (P2, P3) interposed between the condenser (C) and the solenoid valve (XL). The switch (S) is operated by said logic control unit (M) in order to determine, in a first operating condition, the charging of the condenser (C) and, in a second and third operating condition, the application of control voltages with opposite sign from the condenser (C) to the solenoid valve (XL) for the closing and, respectively, the opening of the same solenoid valve. The logic control unit (M) is programmed in such a way that each request for the opening of the solenoid valve brings about the setting of the switch (S) in said first operating condition for the charging of the condenser (C) in first place, then the preliminary activation of the switch (S) in said second operating condition for the closing of the solenoid valve after a first preset time has elapsed since the previous closing control of the same solenoid valve, then again the return of the switch (S) in said first operating condition for the new charging of the condenser (C) and finally the starting of the switch (S) in said third operating condition for the opening of the solenoid valve after a subsequent second preset time shorter than the first one. <IMAGE> |
