GB221128A - Improvements in or connected with mechanism for the conversion of rotary into reciprocating motion - Google Patents

Abstract

221,128. Spence, W. L. May 24, 1923. Machinery, utilizing inertia to obtain movements in. - In mechanism of the paired oppositely rotating bobweight type for converting rotary i n t o reciprocatory motion, applicable to pile-driving hammers &c., the bob - weights are mounted with their axes of rotation in a plane containing the line of reciprocation or in a plane or in closely adjacent planes parallel thereto forming a long as distinguished from a wide disposition, the weights being so matched and paired as to produce when running no unwanted couple or transverse vibration. An arrangement embodying four bob-weights is shown diagrammatically in Figs. 1 and 4 and as applied to a pile-driving hammer in Fig. 9, the bobweights W<1>, W<2>, W<3>, W<4> rotating as indicated by arrows in Fig. 1 so that transverse forces are balanced. The weights are mounted on sleeves E carried by fixed spindles S in a frame K and may be divided and symmetrically staggered (Fig. 4) on each side of the line of reciprocation indicated by worm wheels M, M<1>, adapted to transmit rotation from a worm shaft. L slidably coupled as at Q to a driving motor &c. so as to be adapted to reciprocate with the bob-weight frame K. The intermediate worm and wheel pairs M<1> are oppositely handed to the pairs M in order to drive the corresponding bob-weights in opposite directions. Synchronous running, whereby end thrusts on the worm shaft are eliminated, mav be ensured by interconnecting the bob-weight sleeves E by spur wheel gearing or a thrust bearing or travel limiting collar G may be fixed to the worm shaft L to prevent or limit endwise movement thereof in the bob-weight frame. In the pile driving hammer, shown in Fig. 9, the hammer proper or tup K comprises a cast steel box with a detachably bolted side K<2>, an integral oil bath K<3>, a screw oil feed dipping therein, and with cast standards or brackets F carrying the fixed bobweight spindles E and forming bearings for the worm shaft L. Instead of divided bob-weights as shown, single mass bob-weights may be used arranged all in one plane. The two intermediate bob-weights W<2>, W<3> may be replaced by a single double-weight bob-weight making a three spindle arrangement. Bob-weights shaped as shown in Fig. 9, or of lenticular or other suitable shapes may be arranged in a single plane with the axes of rotation spaced apart at little more than the bob-weight radius.