Rpm detection device and electronic-hydraulic governor null of marine main

摘要

PURPOSE:To provide the actual number of revolutions signal prevailing before no pulse is generated during a failure in operation or disconnection and to enable fixing of the actuator position of a governing device, by a method wherein a memory, a high order priority device, and a comparator are additionally mounted. CONSTITUTION:When two pulse signals from sensors SE1 and SE2 both disappear despite of that rotation of a main engine ENG is normal, an output from a first high order priority device HS1 is reduced. However, a since a preceding output is held by means of a first memory ME1, a second high order priority device HS2 selects it and outputs it as an actual number of revolutions signal. A second comparator CO2 inputs output signals from high order priority devices HS1 and HS2. When an input difference therebetween exceeds a second reference value, it is outputted and therefore, a current actuator position is held by a governing device, and the number of revolutions of a main engine is prevented from a sudden increase. Further, an abnormal detecting signal can be also provided by means of an output from the second comparator CO2.