From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Design for a damped pendulum lever with leaf springs.
| Identifier | ExFiles\Box 17\3\ Scan322 | |
| Date | 18th May 1938 | |
| NSch 2600 THESE NUTS SHOULD BE SCREWED UP HARD IN ORDER TO FLATTEN OUT ALL THE PLATES AND RELIEVE THE CENTRE SECTION OF SPRING OF ALL STRESS DUE TO LOAD APPLIED TO THE ENDS OF THE SPRINGS. AT .500" TRAVEL CP OF BALL PIN THE TOP SLEEVE COMES INTO CONTACT WITH THE INNER PLATES NOTE ASSEMBLE SPRINGS WITHOUT LUBRICANT BETWEEN LEAVES. FRICTION BETWEEN THE LEAVES IS REQD FOR DAMPING. .312 TAPER LEAF SPRINGS WHEN BALL PIN LOAD IS 700 LBS LOAD ON FERRULES A = 610 LBS EACH MOVEMENT OF FERRULES FOR .500 AT BALL PIN = .287" NO. LEAVES = 13 THICKNESS OF ALL LEAVES = .072" STRESS AT 610 LBS = 100 000 LBS/SQ" FREE CAMBER AS SHOWN OR .025" LESS THAN SHOWN TO AVOID THE POSSIBILITY OF SLACKNESS IN MID POSN. ALL LEAVES WHEN FREE HAVE A UNIFORM CAMBER FROM END TO END SEE NOTE RE NUTS CASEHARDEN WEARING SURFACES THE THREE BOLTS BETWEEN THE OUTER PLATES TO BE REAMED PARALLEL FITS. NUTS TO BE WELL TIGHTENED. SPRING MAX LOAD 250 LBS GIVES 40 LBS AT BALL PIN MEAN DIA COILS .850 DIA WIRE .192 NO EFFEC COILS 3.5 DEFLN .275 MAX STRESS 80,000 LBS/SQ" VARY WASHER THICKNESS TO ADJUST SPRING LOAD WHEN THE BEST LOAD IS KNOWN IT MAY BE POSSIBLE TO REDUCE LENGTH OF BOLT FERODO SLEEVES OF STAINLESS STEEL TO OBVIATE RUSTING KELMIT UNLUBRICATED IF THE TRUNNION BLOCK SHOWS SIGNS OF WEAKNESS DUE TO PULL OF LARGE BOLTS EXTRA THICKNESS MIGHT BE OBTAINED BY MAKING THE SLEEVE OF KELMIT INSTEAD OF STEEL PROVIDED THAT KELMIT IS SUFFICIENTLY STRONG TO ACT AS A DISTANCE PIECE 700 LBS + FRICTION SCALE 1/1 DAMPED PENDULUM LEVER WITH LEAF SPRINGS S.S. WGH 18-5-38 | ||