In ordinary gear wheel device, the rotation of the gear wheel or become a symbol of the decline of the Rotary Kiln Shangcuan limit position.Therefore, also known as signal block round.Rotary kiln gear wheel is used to limit (ordinary gear wheel) or control (hydraulic gear wheel) of axial play of the Rotary kiln. In operation, should pay attention to not make the gear wheel or gear wheel for a long time under continuous rotation.Because of this gear wheel device is based only on the Rotary kiln ran principles play a role in the design to prevent.In the vicinity of the two gear wheels fitted with safety limit switch, channeling power when the Rotary kiln is too large gear wheel can not stop, so stop the Rotary kiln main motor power to ensure that the Rotary kiln will not fall down from riding wheel bearing on a significant accident.Gear wheel and tire side to maintain a certain distance U, its value is allowed by the Rotary kiln shell axial movement distance.Its principle is even determine tire and wheel care in the full width of the uniform worn, and the size of the gear meshing well Rotary kiln, Rotary kiln while both ends of the sealing device without losing seal.