GB466789A - Means for driving the shafts of machine-tools at different speeds - Google Patents

Abstract

466,789. Controlling change speed gearing and motors. HERBERT, Ltd., A., and LLOYD, A. H. Dec. 4, 1935, No. 33594. [Class 80 (ii)] [Also in Group XXII] In a variable-speed driving means, different speeds are obtained partly by gearing and partly by an electric motor, the change-speed gearing being preselective with selector and main controls and the variable-speed driving motor being operable from the same controls. The motor, which may be either A.C. with a pole-change device or a resistance-controlled D.C. motor, drives through a four-speed gear, operated by sliding collars 22, 31, Fig. 3, controlling friction clutches, the spindle 35. Slidable yokes 23, 32, engage the clutch collars and these are moved by the engagement of their stems 24, 33 with selected projections on the " preselector " members 43. The latter are adjusted while one gear train is operating by a handle 49, Fig. 4 ; subsequent rotation of a handle 58 closes the members 43 and thus moves the clutch-actuating stems. A further stem 42, Fig. 3, extends within the operating path of the " preselector " and this is moved to control the speeds of the motor through a switch-rod 38. Reversal of the motor is effected by a separate control lever. A two-speed motor is used in the above embodiment to give eight speed changes but other combinations of motor and gear speeds may be employed. Specifications 382,784, 429,741, 434,393, and 441,141 are referred to.