POSITIVE DISPLACEMENT INJECTOR

摘要

A positive displacement injector for automatic centralized lubrication systems is constructed to include a two-piece disk-seal valve assembly that acts as a check valve and also provides seals at oppositely facing surfaces. The assembly consists of a stiff disk sandwiched between upstream and downstream disks of a resilient seal member. Notches in the periphery of the stiff disk are normally blocked by the downstream disk to prevent upstream fluid flow through these notches, yet the periphery of the downstream disk is deflectable to permit downstream fluid flow through the notches when there is relatively high fluid pressure at the inlet port. The assembly is bodily movable so that with low fluid pressure at the inlet port this port is blocked by the upstream disk, and with high fluid pressure at the inlet port the downstream disk blocks axial input to an outlet passage.