抄録
Control of water content in green sand for molding is very important for controlling quality of castings. Precise control of water content has not been performed successfully, however, and the control of water content relies much on experience in the foundry. This presumably is due to the fact that measured figures of return sand before adjustment of water content vary widely microscopically and more sampling is required for the proper determination of water addition. This is a research on the developement of a system to continuously and automatically indicate the required quantity of water addition by improving a conventional continuous water content measuring apparatus. It processes data every 0.1 second and gives the average using a microcomputer. It also controls water content of the mixed sand after mixing within ±0.1% of the projected figure by continuously processing the moldability figure and feeding it back to the microcomputer.
