Abstract: An impact detection system for an industrial door, the system including two members that are releasably coupled to each other to move together with the door as it travels, disposed beyond the doorway opening is a radiation emitter and a radiation detector, preferably packaged together in a photoeye device, and emitting a beam of radiation; the first member carries a reflector that, when the two members are coupled, reflects the radiation back to the photoeye, and that is movable to a position wherein it does not reflect the radiation back to the photoeye in response to separation of the two members caused by the door being impacted, the change in state from 1) the radiation being reflected to the photoeye to 2) the radiation not being reflected to the photoeye thus serves as an indication that an impact on the door has occurred.

Abstract: A roller door sealing system including at least one sealing member carried on the curtain, and disposed adjacent the end of the curtain attached to the roller, and a seal engaging member supported adjacent the curtain. The sealing member and the seal engaging member are disposed such that the sealing member engages the seal engaging member and seals the space between the curtain and the seal engaging member as the curtain approaches the doorway-blocking position. The sealing function provided by the sealing member or members only occurs as the door approaches the door blocking position.

Abstract: An impact detection system for an industrial door, the system including two members that are releasably coupled to each other to move together with the door as it travels; disposed beyond the doorway opening is a radiation emitter and a radiation detector, preferably packaged together in a photoeye device, and emitting a beam of radiation; the first member carries a reflector that, when the two members are coupled, reflects the radiation back to the photoeye, and that is movable to a position wherein it does not reflect the radiation back to the photoeye in response to separation of the two members caused by the door being impacted, the change in state from 1) the radiation being reflected to the photoeye to 2) the radiation not being reflected to the photoeye thus serves as an indication that an impact on the door has occurred.

Abstract: A frost control system is described for inhibiting and removing frost from the door of a storage locker. Relatively cool air is received by an inlet to the frost control system at an inlet placed above the door. The air is drawn into the system by a blower which forces the air through the ducts of the system. The air passes through strip heaters within the vertical ducts of the defrost system positioned on either side of the door. The warm air is discharged horizontally across the bottom portion of the door and simultaneously rises creating a blanket of relatively warm air in comparison to the ambient area. Discharge apertures are included in the ends of the vertical ducts which blow a portion of the warmed air to the base of the door to enhance coverage of the door by the warmed air.

Abstract: A frost control system is described for inhibiting and removing frost from the door of a storage locker. Relatively cool air is received by an inlet to the frost control system at an inlet placed above the door. The air is drawn into the system by a blower which forces the air through the ducts of the system. The air passes through strip heaters within the vertical ducts of the defrost system positioned on either side of the door. The warm air is discharged horizontally across the bottom portion of the door and simultaneously rises creating a blanket of relatively warm air in comparison to the ambient area. Discharge apertures are included in the ends of the vertical ducts which blow a portion of the warmed air to the base of the door to enhance coverage of the door by the warmed air.