GB299488A - Improvements in methods of and apparatus for controlling electrically operated windlasses - Google Patents

Abstract

299,488. Eck, R., and Gõbel, F. A. R. July 8, 1927. Driving-gear for winches. - Electrically-controlled windlasses driven by three-phase asynchronous motors in conjunction with a balancing gear are arranged so as to obviate the necessity of starting the motors under load. In one arrangement, shown in Figs. 1 and 2, one motor l drives a sun-pinion l<1> while the other k drives external teeth on the wheel h. At starting, the two motors are run under no load at equal speeds in opposite directions and under these circumstances no rotation is transmitted to the shaft d carrying the planet pinions and to the winding drum a. One or other of the motors is then slowed down to allow the winding drum to turn slowly in one direction or the other. Finally the slowed drum is reversed to give full hoisting-speed. Where a hanging load is to be raised, an electromagnetic brake e acts on the shaft d until the motor takes up the load. Fig. 3 shows a modified form in which both motors k, l drive sun-wheels and the planets i', i<2> are keyed to a shaft mounted in the wheel b geared to the drum In this case no rotary movement is imparted to the wheel b and the drum so long as both motors run in the same direction at the same speed. Smoothness in working is caused by arranging that the slowing-down action of the drum k shall be performed against the torque of an auxiliary motor s.