| Optical glass is a kind of important material for key components of optical instruments. The weight of the optical glass blocks is directly related to the thickness, curvature, radius of the optical lens, which affects the behaviors of optical instruments. With the continuous improvement of production efficiency, manual weighing and sorting can not meet the production requirements, it is necessary to develop a high-speed and high-precision automatic weighing and sorting technology. Therefore, the automatic weighing and sorting machine of the optical glass blocks has been developed in this thesis.The scheme of the sorting machine system has been worked out in the thesis, which mainly includes mechanical system and measurement & control system. Sorting based on differential weighing principle can control zero drift phenomena effectively and achieves high-precision measurement.Structural design and assemblage of the mechanical system have been completed, mainly including: upper and lower feeding mechanism, weighing mechanism and group mechanism. Upper and lower feeding mechanism has been implemented based on belt drive; weighing mechanism and group mechanism has been implemented based on pneumatics.The hardware and software design of the measurement & control system has been developed in the thesis. There are three parts of the system, which are movement procedure control, measurement system and I/O interface module. Movement procedure control is achieved by using PLC to control Mechanical action; measurement system completes acquisition and processing of the weighing data; the communication between PLC and IPC is connected by the I/O interface module, PLC informs IPC to start sampling simultaneously, and IPC sends the selection result to PLC. The software of IPC has been programmed by LabVIEW, which supplies good interfaces for debugging operation, result display, trouble warning and so on. The results of actual use are: the accuracy of the system is±0.02g, and the rhythm of work is less than 2s / piece. So, the developed system, with higher accuracy and higher efficiency and also with low breakage rate, meets the requirement of automatic weighing and sorting of the optical glass blocks. |
