摘要 |
In a rotary sliding vane pump having a non-circular cam ring which expands and contracts radially, a cheek plate is clamped against the end face of the cam ring and lies in rubbing contact with the rotor and vanes. The cheek plate has a wearing face of low friction material such as bronze. Unwanted wear between the cheek plate and the cam ring due to its expansion/contraction movements is reduced by the provision of one or more areas of hard metal adjacent the cam ring. |