ImprovingthelimitdeviceofcraneandgantryYANGZhongxiao目前许多天车及龙门吊眼位装置大都采用的是重锤式限位器（图1），当吊钩向上提升到极限位置时，碰到杠杆1，重锤2上像触发极限开关3断电，使吊钩停止上升。这种限位装置存在以下缺点。（1）在天车或危门吊行走时，由于吊 At present, many crane and gantry crane eye position device is used in heavy hammer limiter (Figure 1), when the hook up to the limit position, the lever 1, hammer 2 on the trigger limit switch 3 off Electricity, the hook stopped rising. This limit device has the following disadvantages. (1) Crane or gantry crane walking, due to hanging