with that disclosed in the u s pat no 3 599 587 aug 17 1971 of r g greulich to which reference may be had an air tube 30 is attached to the needle threading assist 28 and extends through the bracket arm 16 terminating at a pneumatic pump 32 secured in the standard 14 a main drive shaft 34 is rotatably carried in the bracket arm 16 for imparting the reciprocatory motion to the needle bar 24 the main drive shaft 34 terminates in a hand wheel 36 having a pulley 38 formed therein a motor 40 is provided for driving the sewing machine main drive shaft 34 and the pneumatic pump 32 as shown in fig2 and 5 the motor 40 includes an armature 41 having electrical windings 42 and 43 wound on a shaft 46 having a first end 48 protruding from one end of the motor 40 and a second end 50 protruding from the opposite end of the motor 40 the first end 48 of the shaft 46 has a first overriding clutch 52 arranged thereon the clutch 52 which for example may be a roller clutch no rc 02 made by the torrington company has an annular shape and includes a.