HEIGHT DETECTING APPARATUS

PURPOSE:To simplify the constitution and to improve detecting accuracy by providing a plurality of contact parts in a detecting body at the different phases, and constituting the intervals between the tips and the supporting points of the contact parts so that the intervals become sequentially small. CONSTITUTION:In a height detecting apparatus, a detecting body 20 and a sensor 21 for detecting the moving angle of the detecting body 20 are provided. The height is detected based on the movement of the detecting body 20 from the initial attitude. Two plate-shaped contact parts S1 and S2 in the different phases are provided in the detecting body 20. The intervals between the respective tips and supporting points of the contact parts S1 and S2 are constituted so that the intervals become sequentially small. When the height of a material to be processed is increased, the contact parts S1 and S2 are sequentially brought into contact with the upper part of the material to be treated. Thus, the detecting accuracy can be improved. The detected data of the height detecting apparatus, i.e., the outputs of the output signal of the sensor 21, are periodically changed with the movements of the movement selecting plates. Therefore, the output signals are sampled at a preset period. Then, a plurality of average values can be used as the data corresponding to the height.