Method and devices for driving a damper

摘要

An actuator (1) comprises an electrical motor (10) for driving a damper (3) from a rest position to a stalled position. The damper (3) is biased toward the rest position with at least one spring. A control module (2) is configured to supply, upon activation of the actuator (1), a drive current to the electrical motor (10) for driving the damper (3) from the rest position to the stalled position against a bias force produced by the spring. The control module (2) is further configured to reduce the drive current to a lower level for maintaining the damper (3) in the stalled position when a defined duration of time has elapsed since activation of the actuator (1). Damages to the electrical motor (10) and/or gear trains can be avoided without having to provide any circuitry or sensory equipment for measuring the drive current.

主权项

1. An actuator for a damper in a fluid flow system comprising:
an electrical motor operable in response to a drive current at a first current level for driving the damper from a first position to a second position where it stalls, the damper being biased toward the first position with at least one spring, a data store configured to store a value of a fixed predefined current reduction time, an electronic time measurement module, an electronic current reducing/switching module that is configured to reduce the drive current to a second current level, which is lower than the first current level, and a control module configured to supply, upon activation of the actuator, the drive current at a first current level to the electrical motor for driving the damper from the first position to the second position against a bias force produced by the spring, wherein the control module comprises an electronic current reducing/switching module that is configured to reduce the drive current to the second current level, for maintaining the damper in the second position when the fixed and predefined current reduction time, as measured by the electronic time measurement module, has elapsed since activation of the actuator, wherein the control module comprises a microprocessor and a programmed timer module, the programmed timer module including program code for controlling the microprocessor such that the microprocessor determines the duration of time elapsed since activation of the actuator, compares the duration of time to the predefined current reduction time, and produces a signal for switching the drive current to the lower level when the duration of elapsed time is equal to or exceeds the fixed and predefined current reduction time.