Patent ID: 9732543
Date: 2017-08-15
CPC Classifications: E05B,H01H,H02B,Y10T

Claim:
1. A door interlock device of a vacuum circuit breaker in a power transformer room, the interlock device comprising: a ground switch including a shaft, a cam located on the shaft of the ground switch; a supporter located on a side plate; a slidable shaft located at the supporter and including a first end contacting the cam such that the slidable shaft is movable upward and downward; a spring located within the supporter to provide an upward elastic force to the slidable shaft; and an interlock plate located at one side of a door of the power transformer room and configured to contact the slidable shaft, wherein: the cam includes a groove that is coupled to the shaft of the ground switch; the groove includes a screw groove, the cam is located on an extended line of a length direction of the slidable shaft; the slidable shaft includes a circumferential groove at a central portion and a fixing member at a second end, the fixing member fixing the slidable shaft to the supporter; the fixing member is a ring or a cap that corresponds to a diameter of the slidable shaft; an outer diameter of the fixing member is larger than a diameter of the slidable shaft; the spring is inserted around the slidable shaft and has a first end fixed and supported by a lower surface of a body of the supporter and a second end supported by a key provided at the slidable shaft; the slidable shaft further includes a hole into which a key is inserted; the interlock plate includes a hooking recess that engages the circumferential groove; the hooking recess includes a hooking portion having a width equal to or larger than the diameter of the slidable shaft and an inlet portion having a width larger than a diameter of the circumferential groove but smaller than the diameter of the slidable shaft; the door is prevented from moving when the ground switch is in an open position and the interlock plate is restricted by the slidable shaft; and the door is allowed to move when the ground switch is in a closed position and the interlock plate is not restricted by the slidable shaft.