Device and method for responding to loss-of-brake on a railroad crossing gate mechanism
AssigneeSiemens Mobility GmbH
InventorPaul Young
Life of this patent
Estimating the term…
Abstract
A crossing gate mechanism includes an electric brushless direct current (BLDC) motor with a sensing device, a crossing gate arm operated via the BLDC motor, a motor brake coupled to the BLDC motor, wherein the motor brake is configured to hold the crossing gate arm in a position, and a controller configured to control the BLDC motor, wherein the controller is configured to control the BLDC motor to raise or lower the crossing gate arm in response to a gate control signal, and wherein, when the motor brake fails to hold the crossing gate arm in the position, the controller is configured to control the BLDC motor to hold the crossing gate arm in the position instead of the motor brake.
Claims18
A crossing gate mechanism comprising:
- an electric brushless direct current (BLDC) motor with at least one sensing device,
- a crossing gate arm operated via the BLDC motor,
- a motor brake coupled to the BLDC motor, wherein the motor brake is configured to hold the crossing gate arm in a position, and
- a controller configured to control the BLDC motor,
- wherein the controller is configured to control the BLDC motor to raise or lower the crossing gate arm in response to a gate control signal,
- wherein, when the motor brake fails to hold the crossing gate arm in the position, the controller is configured to control the BLDC motor to hold the crossing gate arm in the position instead of the motor brake, and
- wherein the controller includes a PID (proportional-integral-derivative) controller for a desired position and a desired speed of the crossing gate arm, and wherein the desired position is selected such that the crossing gate arm is held in the position.
A method for responding to loss-of-brake on a railroad crossing gate mechanism, the method comprising:
- raising, by a brushless direct current (BLDC) motor in combination with a controller, a crossing gate arm in a desired position,
- engaging a motor brake for holding the crossing gate arm in the desired position,
- detecting that the motor brake has failed,
- engaging the BLDC motor to hold the crossing gate arm in the desired position instead of the motor brake, and
- providing, by a gate control state machine, the desired position of the crossing gate arm to a PID (proportional-integral-derivative) controller, and
- comparing, by the PID controller, the desired position to an actual position of the crossing gate arm and outputting a desired speed.
Dependencies are inferred from the claim text.