750,828. Sewing-machines. VITTORIO NECCHI SOC. PER AZIONI. Jan. 22, 1954 [Feb. 7, 1953], No. 1960/54. Class 112. [Also in Groups XXXV and XXXVII] A control unit for a sewing-machine comprises a transformer having a primary winding 9 connected to a device 3 with a number of terminals adapted for supply voltages of different values. The driving motor 4 is connected to tappings b1 and e in the primary coil through a change-over switch 5, the tapping b1 supplying the rated voltage to the motor, and the tapping e a reduced voltage. A rheostat 6, which may be combined with a switch for breaking the motor circuit, is connected in series with the motor. The secondary winding f of the transformer supplies a reduced voltage to a lamp 8 for illuminating the work. If a cut-out switch 71 is provided in the primary circuit, the lamp acts as an indicator of the energization of the primary winding. The transformer, cut-out switch, change-over switch, as well as the device 3, may be incorporated in a single unit for mounting on the sewing-machine, the rheostat being contained in a separate housing, Figs. 2-6 (not shown). In a modification, the motor is in the same housing with the transformer and the circuit elements 3, 5, and 71, Figs. 7-10 (not shown).
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