| 摘要 |
<p>A pump suitable for food products containing solid pieces has a rotary turret (11) incorporating four piston and cylinder pumping units (15) spaced uniformly around the rotation axis. The pistons are reciprocated by a stationary cam (8) and have associated with them rolling diaphragms (35) which separate pumping chamber (40) from chamber (41) which are connected to a vacuum source. The cylinders are closed by a rotor end member (50) journalled on a manifold member (60) and provided with fluid ports (51). A sealing ring (65) of low friction material forms a seal with the end face of member (50) and includes slots for connecting the ports (51) alternately to supply and discharge conduits (55, 56) for the product passing through the pump. The sealing interface between member (50) and ring (65) is surrounded inwardly and outwardly by a cavity for receiving barrier fluid, e.g. steam, under pressure. The manifold member (60) can be raised by operating a handwheel (84) to separate the sealing faces to facilitate cleaning/sterilisation. In a modified embodiment the rotor end member includes passages for interconnecting the pumping chambers during cleaning/sterilisation periods, a valve assembly being provided for opening and closing these passages.</p> |
