GB989289A - Improvements in or relating to pivotally connected members - Google Patents

Abstract

989,289. Pivots. WILKENSON SWORD Ltd., and H. B. RANDOLPH. Feb. 8, 1962 [Dec. 19, 1960], No. 43584/60. Heading E2F. In scissors, shears or pruners in which a pivot pin secured to one of the blades extends through a sleeve secured to the other blade coaxial with the pivotal axis of the blades, the pin and sleeve co-operate to form a bearing whose axial length is a multiple of the thickness, adjacent said axis, of said other blade. In the shears shown in Fig. 1, a pivot pin 11 has a non-circular portion 11c lying within a corresponding aperture in the blade 12 and a sleeve 14 fitting around the stem of the pin has a non-circular portion 14a fitting in a corresponding aperture in the blade 13. The pin has a further non-circular portion 11d over which is fitted a bush 15 having a skirt 15a which embraces a reduced portion 14b of the sleeve 14 with the interposition of a bearing 16. A handle 20 is attached to the bush 15 or skirt 15a whilst another handle 21 is attached to the sleeve 14. A lock washer 18 is keyed to the pin 11 and has peripheral tabs 18a which may be bent upwards into one of a plurality of recesses in a nut 17 the number of tabs differing from the number of recesses so that the nut may be finely adjusted. A peripheral portion of a shoulder 14c of the sleeve is cut back to form a keyway and a portion of the skirt 15a of shorter peripheral length is extended as a key into this keyway so that the angular movement of the blades is correspondingly limited. A spring may be incorporated between the relatively movable parts of the pivot assembly. The blades may be extended rearwardly beyond the pivot and the handles connected directly to the blades. In a modification, Figs. 5 and 7, the pivot pin 11<SP>1</SP> is tubular and is secured to the blade 13<SP>1</SP> whilst the sleeve 14<SP>1</SP> is secured to the blade 12<SP>1</SP>. Handle 20<SP>1</SP> is secured to the sleeve whilst handle 211 extends through a slot 14<SP>1</SP>c in the sleeve and is secured to the pivot pin. In another modification, Fig. 9, the blades 12<SP>11</SP> and 13<SP>11</SP> are secured to a tubular pivot pin 11<SP>11</SP> and a sleeve 1411 respectively. The pivot pin is extended axially beyond the sleeve and handle 20<SP>11</SP> is secured to the extended portion whilst handle 21<SP>11</SP> is secured to the sleeve. To bias the blades and handles to the open position, a spring 35 has its opposite ends engaging the pin and sleeve respectively.