METHOD FOR PREVENTION OF ICING OVER SHAFT VENTILATION FOLDING DOOR OF SUPPLY CHANNEL Russian patent published in 2010 - IPC E21F1/14 

FIELD: mining.

SUBSTANCE: previously frame is prepared for heating with the help of flexible heating element, which is arranged along perimetre of outer or inner surface of frame with fixation on it. Afterwards heating element via terminal box arranged inside connecting box is connected to sensor for control of air temperature supplied to area of frame location. Sensor is connected to source of power supply. Area of sensor location together with connecting box is a section of frame, towards which largest part of cold atmospheric air flow is directed in process of reverse. Under conditions of negative temperatures, prior to reversing of ventilation jet at specified time by actuation of air temperature control sensor, heating element is connected to source of power supply, providing for preheating of supply channel folding door frame. As ventilation jet is reversed with supply of cold atmospheric air, channel folding door is transferred to position of reverse mode with the possibility of adjacency to heated frame. At the same time frame heating is continued, and heat is transferred from frame to folding door, preventing its icing. As time of ventilation jet reversing elapses, frame heating is stopped by de-energising of heating element. Then since channel folding door will not freeze to frame, it is freely changed into initial position. Prevents icing of folding door in supply channel during ventilation jet reversing under conditions of negative temperatures.

EFFECT: heating of supply channel folding door as it adjoins heated frame in reverse mode position.

6 cl, 4 dwg