| 摘要 |
Described herein is a device for engaging power takeoffs primarily used to drive a load from the engine of a vehicle, having an electromagnet (11) with a single winding of small size which is driven by a microprocessor system (32) in PWM mode allowing to differentiate the current intensity of the engaging phase (Im1) and of the phase of maintaining said engaging (Im2). The control system maintains monitored, without the aid of external sensors, some parameters such as electromagnet current, power supply and electromagnet voltage, electromagnet winding resistance, electromagnet winding inductance. From these parameters, the system is able to determine the engaging or unengaging position of the power takeoff, and it is able automatically to uncouple if the monitored parameters do not fall within the expected ranges, simultaneously notifying the user of the protective intervention. |
