| 摘要 |
556,786. Control of D.C. motors. BRITISH THOMSON-HOUSTON CO., Ltd., and BUTLER, F. E. May 26, 1942, No. 7131. [Class 38 (iii)] Six traction motors are started in series and resistors excluded by forward movement of one cam-shaft, the motors are then regrouped into three parallel sets of two motors each with the original and additional resistors, the additional resistors are excluded by another cam-shaft and then the original resistors by backward movement of the first cam-shaft. First series position is given by closing switches 7, 15, 9, 16, 10, 17 and 8. Resistors R1-R2, R4- R5, R-6-R7, are excluded by the first camshaft to full series position in which switches 18, 19, 20 and 21 are closed. Transition to first parallel is given by closing switches 11, 12, 13 and 14 after opening 15, 9, 16, 10 and 17. The second cam-shaft then excludes resistors R1-R3, R4-R9, R10-R11, and R7-R8 and thereafter the first cam-shaft reverses and reexcludes resistors R1-R2, R4-R5 and R6-R7 tc give full parallel position. Specification 329,336, [Class 38 (iii)], is referred to. |
