| 摘要 |
PURPOSE:To smoothen the variable speed operation by controlling the angle of inclination of a variable capacity pump provided on an output shaft by a shifting signal, driving a constant capacity motor mounted on an input shaft by a discharge pressure and synchronously rotating the input shaft and the output shaft. CONSTITUTION:When a main clutch 14 is cut and a shift lever 22 is shifted to a desired variable speed position, a shift detector 23 detects the shifting and a desired speed reduction ratio signal rhoD is supplied to a control circuit 24, and the output (e) of an operation circuit 26 assumes a new value. This value is supplied to a swash plate angle setting circuit 27 and a short-circuit signal generating circuit 25. As a result, the short-circuiting of a variable capacity pump 17 is released by a signal (a) and the angle of inclination of the swash plate of the variable capacity pump 17 is moved in a direction in whch braking is applied to a hydraulic motor 16 by a signal (b). The ratio rhoO between the rotation of the main shaft 4 and that of the auxiliary shaft 8 is reduced by this hydraulic motor 16 and approaches a value identical with that of the desired speed reduction ratio signal rhoD. By these procedures, a smooth shifting becomes possible. |
