GB796243A - Engine starter coupling mechanism - Google Patents

Abstract

796,243. Engine starting mechanism. BENDIX AVIATION CORPORATION. May 14, 1956 [May 23, 1955], No. 14974/56. Class 7(5) In an engine starting mechanism including an engaging member for engaging an engine part, means operably connecting the member to a drive member and comprising a barrel member and a screw member helically engaged in the latter and means for causing the screw member to be advanced out of the barrel member upon rotation of the latter to cause engagement of the engaging member with the engine part, the means causing advancing comprises weighted tooth means pivoted to the barrel member and co-operating with complementary toothed means about the screw member to exert a drag upon the latter so that the latter is advanced axially upon rotation of the barrel member. Referring to the Figs., upon rotation of the shaft 1 the barrel and screw members 3, 14 are carried around with it. The heavy lugs 23 because of their inertia do not accelerate as rapidly as the barrel member and as a result the lugs turn on their pivots in the direction of the arrow (Fig. 2). This effects a dragging action upon the screw member whereupon the latter is caused to travel axially outward. As the latter so moves the starter jaw is advanced by it into engagement with the opposed engine jaw. When the engine has started the motive power to the drive shaft is cut off. As the engine rotates at high speed (which may be 18,000 r.p.m.) the lugs 23 tend to swing centrifugally in a counterclockwise direction (Fig. 2). As the faster rotating engine jaw releases itself from the starter jaw the reaction effected on the screw member by the centrifugally acting lugs causes the screw member to be returned to disengaged position in the barrel member. Projecting from the inner face of each lug is a pin 33. The periphery of a ring spring 34 limits against the underside of each pin This serves to effect a slight radially directed tension whereby chattering of the lugs is avoided. As shown, the barrel member 3 is connected to the shaft 1 by a slip clutch 4 of disc pack type. There are four lugs 23 equally spaced.