Improvements in fluid control devices

摘要

An insert 10 is provided for a fluid control device, such as a pump. The insert which may be metal such as brass, is designed to be integrally attachable to a body 13 of the device, which may be plastics material such as acytal. The insert comprises formations 12, conveniently screw threads, for enabling the device to be connected to a supply of fluid. The insert comprises an axially extending annular recess 17, which forms an axially extending ring of plastics material which allows the interface to compensate for differences in coefficients of thermal expansion of the different materials whilst maintaining a permanent watertight connection. The insert is preferably keyed to provide an irregular configuration to the contacting surface between insert and the body of the device; this may comprise undercut regions 14 and circumferential components (16, fig 1) extending parallel to the longitudinal axis of the insert to improve resistance to torsional forces.