US 11,708,722 B2
Apparatus and methods for door curtain breakaway detection
Ryan P. Beggs, Dubuque, IA (US); Michael Sivill, Dubuque, IA (US); Christopher Saleh, Ames, IA (US); Charles Runde, Hazel Green, WI (US); James Pelegrin, Dubuque, IA (US); Nicholas J. Casey, Cascade, IA (US); and Perry W. Knutson, Lancaster, WI (US)
Assigned to RITE-HITE HOLDING CORPORATION, Milwaukee, WI (US)
Filed by RITE-HITE HOLDING CORPORATION, Milwaukee, WI (US)
Filed on Sep. 9, 2020, as Appl. No. 17/16,019.
Claims priority of provisional application 62/897,790, filed on Sep. 9, 2019.
Prior Publication US 2021/0071476 A1, Mar. 11, 2021
Int. Cl. E06B 9/58 (2006.01); E06B 9/13 (2006.01); E06B 9/68 (2006.01)
CPC E06B 9/581 (2013.01) [E06B 9/13 (2013.01); E06B 2009/585 (2013.01); E06B 2009/6827 (2013.01); E06B 2009/6836 (2013.01); E06B 2009/6845 (2013.01)] 18 Claims
OG exemplary drawing
 
1. An apparatus comprising:
a door curtain for a door, the door curtain to extend into a channel of a guide for the door curtain through a gap defined along the guide;
a plurality of alignment features to be distributed along the door curtain adjacent a lateral edge of the door, the lateral edge of the door curtain to be farther away from a center of the door curtain than the alignment features are from the center of the door curtain, the plurality of alignment features and the lateral edge of the door curtain to travel within the channel of the guide as the door curtain moves between an open position and a closed position, the alignment features to protrude away from both a front side and a back side of the door curtain to define a dimension of the alignment features, the gap dimensioned to be less than the dimension of the alignment features to help retain the lateral edge within the channel of the guide;
a sensor to be mounted on the guide at a position to detect at least one of the alignment features on the door curtain as the alignment features pass the sensor during an operational state of the door curtain; and
a controller to identify when the door curtain transitions from the operational state to a breakaway state based on a signal from the sensor, the operational state corresponding to when the lateral edge of the door curtain is enclosed within the channel of the guide as the door curtain moves between the open and closed positions, the breakaway state corresponding to when a portion of the lateral edge of the door curtain below an upper end of the guide breaks away from the guide.