AUTOMATIC TRIMMING SYSTEM

摘要

A control for adjusting the trim of a motor boat having a drive unit mounted on the boat for adjustment of the thrust angle relative to the boat. A trim motor adjusts the drive unit relative to the boat. A boat speed responsive pick up and control provides an output signal indicative of boat speed. A microprocessor controls the trim motor and is connected to receive the speed signals. The microprocessor reads boat speed at intervals and compares the latest speed reading with the prior reading to determine whether boat speed is increasing. The microprocessor commands the trim motor to move the drive unit in increments in one direction so long as each adjustment results in increasing speed and then to move the trim motor to adjust the drive unit in increments in the opposite direction so long as the adjustment results in increasing speed. The microprocessor hunts for optimum adjustment by adjusting the drive unit in both directions until boat speed has been maximized, or nearly so, and then stops adjusting the drive unit. The microprocessor delays hunting for maximum boat speed until boat speed is constant following activation of the control. There is a time delay following each adjustment of the drive unit before present boat speed is determined for comparison with the prior speed reading.