GB118098A - - Google Patents

Abstract

118,098. Michell, A. G. M. July 19, 1917, [Convention date]. Actuating pumps by fluid-pressure motors; valve-actuating arrangements.-A device for converting reciprocating into rotary motion or vice versa, applicable to air or gas compressors, pumps, &c., comprises an oblique swash plate 1 fixed to a shaft 2 and formed with plane faces engaged on one or both sides by slipper blocks 11, 12 connected by ball joints or other universal joints to reciprocating members, such as pistons 5, 5<A>. If the shaft is intended to rotate in one direction only, each block is jointed at a point behind its centre, as shown in Fig. 5, to allow a wedge-shaped film of lubricant to be formed between the bearing surfaces; for the same purpose the blocks 11, 12 may have relatively weak or flexible portions on one or both sides. The blocks are adjusted to take up wear by means of caps 12 screwing into the ends of the pistons 5 and locked by set-screws. Rotation of the blocks is prevented by projecting rings on the plate 1 in proximity to the inner curved edges of the blocks, or by projections 55, Fig. 5, engaging slots 53 in bars 8 which connect together pairs of pistons 5, 5<A>; a stud 54 fixed to the casing prevents rotation of the pistons. Fig. 4 shows the application to a steam-driven air compressor. Steam is admitted to a series of cylinders 6 by a rotary valve 34 on the shaft 2 and exhausts through openings 40. The steam pistons 5 are connected rigidly by bars 8 to pistons 5<A> in the compressing cylinders 6<A>. which are controlled by a rotary valve 26 on the shaft 2. To reduce clearance space, projections 29 on the pistons extend into valve ports 27. In the case of a single piston with a slipper block engaging one face of the plate 1, the return stroke of the piston may be effected by a spring placed in the cylinders or by pressure of the working fluid or by adhesion of the oil film between the block and the plate. The two faces of the plate need not be parallel, in which case the reciprocating members on the two sides have strokes of different lengths. The shaft 2 may be extended as shown at 2A in order to transmit power.