| 摘要 |
PURPOSE:To perform contactless multistage change-over of speed of a DC motor by controlling input of IC's of a decorder by a method wherein the bias of a transistor for detection is connected to output of the IC's of the decorder through plural series circuts consisting of a diode and a resistor respectively. CONSTITUTION:At a device to control a transistor Q2 for feed control by output of the transistor Q1 for detection, the base bias of the transistor Q1 for detection is connected to respective outputs of the decoder ICX through the plural number (n) of series circuits consisting of respectively the diodes D1-Dn and the resistors R1-Rn. By controlling inputs of the decorder ICX thereof, the base bias of the transistor Q1 for detection is changed over the multistage, and contactless multistage change-over of speed of the DC motor M is performed. |
