GB652690A - Improvements in or relating to chain and sprocket transmissions - Google Patents

Abstract

652,690. Driving chains. RADDINGS, J. E., and PEARSE, P. L. Dec. 19, 1947, Nos. 33701/47, 33702/47 and 8683/48. [Class 24] [Also in Groups XXIV and XXXIII] In a chain and sprocket movement transmitting system, such as used in aircraft for operating control surfaces the chain is provided of asymmetrical formation and cooperates with means on the sprocket for preventing incorrect engagement. As shown in Fig. 7 the side links 10 of the chain are connected by a bridge piece 12 and washers or heads 13 are provided on the connecting pins and the sprocket 16 is provided with a disc 17 secured thereto. The washer 13 cannot enter the space 20 between the sprocket and disc 17 and the bridge piece 12 prevents engagement when presented to the sprocket so that only in the attitude shown will the chain engage correctly. In Fig. 11 in addition to a bridge piece 12 a lateral projection 10c is provided from one side link which co-operates with projections 22 on one side of the sprocket and in Fig. 14 an extension 10d of one side link co-operates with an annular shoulder 16a on the sprocket. In Fig. 15 a transverse projection 112 on one side link forms the bridge piece and another transverse projection 110c or an extension 110d on the same link co-operates with projections or a shoulder on the sprocket. Fig. 22 side links of triangular form have their apices 32, 33 oppositely directed so that engagement with the sprocket 16 is prevented by a shoulder 16a if the chain is not correctly disposed. Alternatively, Fig. 27, the links may have laterally projecting lugs 42, 43 which co-act with a shroud or disc 17 formed on or secured to the sprocket 16.