Tool wear detecting system for a numerically controlled machine tool

摘要

A numerically controlled machine tool controls the movement of a tool relative to a workpiece along a commanded path to cut the workpiece and to detect a load on the tool or workpiece. A specified position or section on the commanded path is the point at which the load on the tool or workpiece is detected and stored. Subsequently, the load on the tool or workpiece is detected each time the tool passes through the specified position or section and this detected value is compared with the above stored content. When the difference is larger than a predetermined value, an alarm signal is produced to indicate that the tool has worn out.