摘要:
A device and a method for the control and monitoring of a deflectable electron beam is provided for the working of metal wherein the electron beam is not permitted to go beyond an allowed working area. With this device with the aid of a Teach-In method the limits are entered into a computer. The computer generates an image of the areas allowed for the electron beam in a particular area of a special memory. This memory is so organized that the addresses of the point of the particular areas correspond to the digitized coordinates of the point of impingement of the electron beam. The characterization of the allowed and forbidden target points of the electron beam takes place through placing or deleting respectively the assigned bits in the special memories.
摘要:
Apparatus for controlling the distance of a melting electrode from the surface of melted material in a vacuum arc furnace which uses short circuits caused by the droplets between the melting electrode and the surface of the melted material as a control criterion. The short circuits occurring within a given period of time--the so-called droplet rate--are determined and supplied to an averager which is connected with a controller that controls an electric driving mechanism for the melting electrode. According to the invention, the controller is responsive to a signal representing the difference between the reciprocal value of the droplet rate signal formed by the averager and a desired time, this desired time being equal to the desired average time between two consecutive droplet short circuits.