Device and method for measuring engagement lengths of locking elements of elevator doors

The invention discloses a device and a method for measuring engagement lengths of locking elements of elevator doors. Based on the capacitive gating sensing technology, the device and the method are achieved by using an arranged door lock on/off signal acquisition circuit to trigger a measurement display circuit to enter a hold mode to lock measurement data. The device comprises the door lock on/off signal acquisition circuit, an outer casing, a pen-shaped meter, a movable ruler, a static ruler, a level bubble, a capacitive gating sensor, the measurement display circuit and keys. The door lock on/off signal acquisition circuit is connected with the pen-shaped meter and the measurement display circuit respectively; and the static ruler penetrates through the outer casing and is embedded in a groove of the movable ruler, and the movable ruler and the movable ruler fixing part can move on the static ruler through the movable ruler groove. According to the device and the method for measuring engagement lengths of locking elements of elevator doors, engagement lengths can be measured simply, conveniently and rapidly while only one value is needed to be measured, defects in prior methods are overcome, and accordingly, inspection personnel can determine whether elevator doors are locked accurately and rapidly.