GB704902A - Improvements in or relating to compressors for air or other gaseous fluid - Google Patents

Abstract

704,902. Compressors. RICARDO & CO., ENGINEERS (1927) Ltd., and RICARDO, H. R. July 16, 1952 [Aug. 8, 1951], No. 18655/51. Class 8 (1). A reciprocating compressor has a cylindrical valve member and housing arranged for relative rotation for controlling admission and delivery ports in their cooperating cylindrical walls, and also for relative axial movement for varying the points of opening of both the admission and delivery ports without changing their points of closing, said axial movement being effected automatically by variations in the relationship between the admission and delivery pressure. The compressor comprises a pair of cylinder blocks A, A<SP>1</SP> each having a plurality of parallel cylinders A<SP>2</SP> disposed around a rotary distributing valve K and containing double-acting pistons G connected in pairs by piston rods G' passing through elongated guides F in the ends of the cylinders and actuated by a wobble plate H<SP>1</SP>. The latter is journaled on bearings H<SP>2</SP> carried by a member H<SP>3</SP> secured to a main driving shaft H<SP>4</SP>. The piston rods each have a cylindrical housing G' for a rockable member G<SP>3</SP> bored to receive a pin H projecting from the wobble plate. One of the housings G<SP>4</SP> has end caps to prevent its member G' from sliding axially therein and so prevent the wobble plate from rotating; the other housings are open-ended to allow free transverse movement of their inner members. Combined inlet and discharge ports J are disposed at each end of the cylinders and cooperate with inlet ports K<SP>6</SP> K' and discharge ports K<SP>4</SP>, K<SP>5</SP> in the rotary valve. The inlet ports in each valve communicate permanently with an inlet passage L and the discharge ports with a discharge passage D'. The valves which are driven from the shaft H<SP>4</SP> are slidable axially thereon and are biased outwardly by springs M. If the discharge pressure in the passages D' increases, the valves are moved axially against their springs and the co-operating ports in the cylinders and the valves are so shaped that the opening of the ports is retarded and hence the discharge pressure from the cylinders is increased. The piston rods G<SP>1</SP> are a close sliding fit in the guides F which maintain the pistons G substantially out of contact with their cylinders. Annular grooves are provided on the pistons and on the surface of the rotary valves to form a labyrinth packing. An annular cham- .ber F<SP>6</SP> is provided in each of the guides F to which lubricant-laden air has access through passages F<SP>5</SP>. Balancing members N<SP>2</SP> are provided on the main shaft to counteract the effect of the wobble plate. Specifications 704,903 and 704,935 are referred to.