Lift gates and related control systems and methods
AssigneeLeonard Automatics, Inc.
InventorsJeffrey N. Frushtick, Bradley D. Hamrick
Life of this patent
Estimating the term…
Abstract
A gate system and related control systems and methods include a frame assembly and a tracking assembly coupled to the frame assembly. A door is in mechanical communication with the frame assembly. Related methods for operating a gate of a gate system, where the gate is set to manual mode to manually open or close the gate. Additionally, control systems include a fail-safe programmable logic controller (PLC) circuit for controlling the gate for opening and closing a gate that employs redundant fail-safe features. The control system includes a safety PLC circuit having a PLC including a first input terminal and a second input terminal, and a light curtain switch electrically coupled to the first and second input terminals.
Claims20
A gate system, comprising:
- a frame assembly;
- a tracking assembly coupled to the frame assembly;
- and
- a door in mechanical communication with the frame assembly via a pair of linear actuators and the tracking assembly via a guide rail engaging a track roller, the linear actuators and guide rail cooperating simultaneously with the door to rotate the door about an axis extending horizontally through the frame assembly.
A method for operating a gate in a manual mode by a user, said method comprising:
- initiating the manual mode to manually open or close the gate;
- determining that the user has pressed a gate close input button;
- closing the gate in response to the gate close input button being pressed;
- periodically determining whether the gate has reached a fully closed position;
- determining whether the gate close input button is still being pressed if the gate has not reached the fully closed position;
- and
- stopping closing the gate if the gate close input button is not being pressed or the gate has reached the fully closed position.
A fail-safe programmable logic controller (PLC) circuit for controlling a gate, said PLC circuit comprising:
- a PLC including a first input terminal and a second input terminal;
- a light curtain switch electrically coupled to the first and second input terminals, said light curtain switch configured to be responsive to a signal from an optical light curtain device that is configured to detect an object in a light curtain, wherein the light curtain switch transmits a stop signal to stop movement of the gate in response to the signal from the optical light curtain device;
- a bump strip switch electrically coupled to the first and second input terminals, said bump strip switch being responsive to a signal from a bump strip on the gate that indicates that the gate has hit something to stop movement of the gate;
- and
- a laser camera switch electrically coupled to the first and second input terminals, said laser camera switch being responsive to a signal from a laser camera that indicates that an item is in a travel area of the gate to stop movement of the gate.
Dependencies are inferred from the claim text.