GB1299751A - Modifying the piston reciprocation in prime movers - Google Patents

Abstract

1299751 I.C. engines with hydraulic drives H KRESS 26 Jan 1970 [27 Jan 1969] 3641/70 Heading F1B In a prime mover, e.g. an I.C. engine, in which the reciprocating motion of the working piston 2, Fig.1, is -converted into rotary motion of mainshaft 9 by the action of a quantity of interposed liquid 6, e.g. oil, on a sealed eccentric 8, the effective quantity of the liquid between transmission piston 4 and eccentric 8 can be varied cyclically by a control piston and cylinder arrangement 11, 12, or by moving a wall portion 7 or varying the total quantity of liquid present. In a two-stroke engine, the piston 12 may be driven, e.g. by the engine, at twice engine speed and commence its liquid extraction strokes slightly before, after or when the piston 2 commences its downward and upward strokes, to cause the piston 2 to spend longer in the bottom region of its cylinder 1. In a four-stroke engine the length e of crank 16 may be reduced cyclically at half engine speed to reach zero or a negative value as the piston 2 completes its exhaust stroke, so that the latter is effectively shortened to prevent the piston from fouling the valves. In an alternative embodiment, Fig.2 (not shown), a double-acting transmission piston (4a) attached to working piston (2), has both ends of its associated cylinder communicated through passages (18, 19) with both ends of cylinder 11a containing a double-acting control piston (12a), and with the spaces at both sides of a sealed eccentric (8). In either embodiment the control piston may be housed in the eccentric.