초록 ▼

A drive circuit including a motor for positioning a damper from a rest position to a stalled position and protect the drive mechanism from damage due to increased current to the drive motor when the damper stalls by including a current limiter to prevent the current in the motor from exceeding a pre

A drive circuit including a motor for positioning a damper from a rest position to a stalled position and protect the drive mechanism from damage due to increased current to the drive motor when the damper stalls by including a current limiter to prevent the current in the motor from exceeding a predetermined value.

대표청구항 ▼

1. A method for controlling a drive motor that is coupled to a damper that has a closed position and an open position, wherein the damper is biased toward the closed position with one or more springs that produce a relatively linearly increasing bias force as the damper moves toward the open positio

1. A method for controlling a drive motor that is coupled to a damper that has a closed position and an open position, wherein the damper is biased toward the closed position with one or more springs that produce a relatively linearly increasing bias force as the damper moves toward the open position, the drive motor driving the damper toward the open position against the bias force, the method comprising:providing drive power to the drive motor to move the damper toward the open position against the relatively linearly increasing bias force, the drive power increasing relatively linearly with a slope as the damper is moved toward the open position to overcome the relatively linearly increasing bias force of the one or more springs; determining when the drive motor stalls at a stalled position by detecting an increase in drive power that is not consistent with the slope of the drive, power; and when the determining step determines that the drive motor has stalled, reducing the power provided to the drive motor. 2. The method of claim 1 wherein the determining step determines that the drive motor has stalled at the stalled position when the increase in drive power that is not consistent with the slope of the drive power continues for a period of time.3. The method of claim 1 further comprising the step of repeating the providing and determining steps one or more times before reducing the power provided to the drive motor.4. The method of claim 1 wherein the reducing step reduces the power supplied to the drive motor to a level that is adapted to maintain the damper at or substantially at the stalled position against the bias force of the one or more springs.