Pump assembly for liq. fuelled domestic burner - comprises rotating piston with position adjustment for low flow rate

摘要

A domestic boiler is supplied with a combustible liquid by a pump which operates at low flow rates as would be demanded during the night. This is obtained by a piston assembly rotating in a cylinder. A pump comprises a casing (10) in which a piston (20) rotates when driven by a motor (27) with a fan (40) attached. The piston head (21) has a cut away annular section which pumps the liquid from an inlet (11) to an outlet and towards the burner. A cam (23) on the piston head acts against a spring (15) via a ball (14) and adjustable stop (13). This allows the flow rate to be adjusted by movement of the piston track and consequently the volume of the piston chamber (25).