Hot-gas reciprocating machine

Abstract

A hot-gas reciprocating machine comprises two intercommunicating spaces of variable volume and two pistons (1 and 11) for varying the volumes of these spaces. The two pistons are coupled to two parallel crank shafts (16 and 17) and are movable with an adjustable phase difference. For balancing the engine a system of counterweights is provided comprising a counterweight (30, 31) on each crank shaft and a counterweight (32, 33) on each of two auxiliary shafts (26, 28) which are coupled one to each crank shaft for rotation therewith at the same speed as and in the opposite direction, each auxiliary shaft extending parallel with the associated crank shaft on the side thereof remote from the other crank shaft. The counterweight on each crank shaft is so arranged that the centrifugal force of that counterweight in the operation of the machine equal half the force produced by the reciprocating parts coupled to the respective crank shaft, and the counterweight on each auxiliary shaft is so arranged that the horizontal and vertical components of the centrifugal force of that counterweight always act respectively in the opposite direction to and the same direction as the corresponding components of the centrifugal force of the counterweight on the associated crank shaft.