GB645635A - Improvements in or relating to engine starters - Google Patents

Abstract

645,635. Turning gear. BENDIX AVIATION CORPORATION. June 21, 1948, No. 16669. Convention date, June 27, 1947 [Class 7(v)] In an engine starter comprising a jaw element 10 adapted to be axially moved into engagement with a jaw member 12 of an engine to be started and to be rotated after its axial movement in order to rotate the jaw member, there is provided inertia means, such as a flywheel part 26; in dynamically balanced association with the jaw element 10 and operative to restrain the element against positive rotative acceleration until the axial movement is effected. An axially-stationary nut 14 is in threaded relationship with the axiallymovable screwshaft 16, the forward end of the screwshaft being spined to the element 10, which latter incorporates the flywheel part 26. The nut 14 is driven through planetary gearing 44 in engagement with an orbital gear 48 connected by an adjustable multi-plate friction clutch 50 to the starter housing as well as a sun gear 46 on the armature shaft 70. A partition 64 in the housing supports a seal 66 and a bearing 68 for the shaft 70. The element 10 is held to the screwshaft 16 by a stud 74 having a flange 76 compressing a seal 78 in a central web of the jaw element, whilst coil spring 85 is compressed between the stud flange 76 and an internal screwshaft flange. The element 10 is provided with a seal 86 engaging an inner extended part of the element, the seal being secured to a casing part 34. When nut 14 is rotated the screwshaft moves leftwardly and due to the inertia of the jaw element the latter does not rotate but is moved axially by the spring 85 into mesh with the member 12, at which time shoulders 90 and 92, on the screwshaft and nut, respectively, come into engagement whereupon the element 10 is then rotated to crank the engine. In a modification, the flywheel part is made integral with the screwshaft, which latter has a splined connection with the jaw element, whilst an oil seal is located in the inner end of the bore of the nut. A retaining nut is also provided on the inner end of the screwshaft so that the latter may be assembled in the driving nut, and the screwshaft has vent spaces therein to prevent a dash-pot action between the driving nut and itself. The jaw element seal may be dispensed with, and a seal located around the driving nut instead. In another modification, the flywheel part and screwshaft are separate, both being splined to the jaw element, whilst a spring is situated between the flywheel part and the jaw element instead of around the stud.