Barrier operator with fault control

• US 6,737,821 B1
• Filed: 08/31/1999
• Issued: 05/18/2004
• Est. Priority Date: 04/09/1991
• Status: Expired due to Fees

• Current Assignee: The Chamberlain Group, Inc. (The Chamberlain Group LLC)
• Original Assignee: The Chamberlain Group, Inc. (The Chamberlain Group LLC)
• Inventors: Fitzgibbon, James J., Willmott, Colin B.
• Primary Examiner(s): Salata, Jonathan
• Application Number:
  US09/387,659
• Time in Patent Office: 1,722 Days
• Field of Search: 318/280-286, 318/466-470, 318/256, 318/265, 318/461, 318/463, 47/26, 47/28, 471/18, 471/41, 160/292, 160/293.1, 361/23, 361/25, 361/37
• US Class Current: 318/280
• CPC Class Codes: E05F 15/41 Detection by monitoring transmitted force or torque E05F15/48 takes precedence; Safety couplings with activation dependent upon torque or force, e.g. slip couplings
• CPC Class Codes: E05F 15/668 for overhead wings
• CPC Class Codes: E05F 15/79 using time control
• CPC Class Codes: E05Y 2400/10 Electronic control
• CPC Class Codes: E05Y 2400/554 sensing motor load
• CPC Class Codes: E05Y 2800/00 Details, accessories and auxiliary operations not otherwise provided for
• CPC Class Codes: E05Y 2800/21 of identical elements, e.g. of identical compression springs
• CPC Class Codes: E05Y 2800/246 with at least one element being redundant
• CPC Class Codes: E05Y 2900/106 for garages
• CPC Class Codes: G05B 19/4062 Monitoring servoloop, e.g. overload of servomotor, loss of feedback or reference
• CPC Class Codes: G05B 2219/42321 Wrong direction or sign of measured value, eventually stop
• CPC Class Codes: G05B 2219/45242 Door, panel, window operation, opening, closing
• CPC Class Codes: H01H 47/002 Monitoring or fail-safe circuits
• CPC Class Codes: H02H 7/0851 for motors actuating a movable member between two end positions, e.g. detecting an end position or obstruction by overload signal

Abstract

A garage door opening and closing apparatus having improved operational safety includes a control circuit which responds to a number of input stimuli to generate commands to open and close a garage door as well as to stop garage door movement. Three relays respond to the commands via drive circuitry to actually connect door operating voltages to the windings of a door controlling motor. By redundancies in the operation of the three relays, faults in the operation of those relays result in safe door operating conditions. Additionally, the control circuitry upon issuing a door stop command, performs a test to determine whether or not the door is still moving. If the door is still moving, door up commands are generated by the control circuitry to place the door in a safe position.

Claims

1. In a movable barrier operator comprising a movement control apparatus for controlling movement of a barrier in response to commands, the method comprising:

sending a command to the movement control apparatus specifying one of open, close, or stop movement of the barrier;

checking the movement control apparatus to determine whether the command is being correctly performed;

generating a signal when the checking step determines that the command is not being correctly performed; and

controlling barrier movement in response to the generated signal.

2. A method according to claim 1, wherein a stop command is sent to the movement control apparatus thereby directing the barrier to stop, and the checking step checks the movement control apparatus to identify whether the barrier has stopped.

3. A method according to claim 2, wherein an open command is generated directing the opening of the barrier if the checking step indicates that the barrier has not stopped.

4. An apparatus for controlling a movable barrier operator, the apparatus comprising:

a controller for sending commands to a movement control apparatus specifying one of open, close, or stop movement of the barrier;

the movement control apparatus for controlling barrier movement in response to the commands sent by the controller and in response to signals generated by a fault identifying apparatus; and

the fault identifying apparatus for checking the movement control apparatus to determine whether the command sent from the controller is being correctly performed and for generating a signal when the command is not being correctly performed.