Abstract: The pressure limiting device is used with a diaphragm pump for controlling the forces applied to the diaphragm. The device includes a body having a pressure control chamber therein. The body has an inlet to the chamber which is adapted to be coupled to a working chamber in the diaphragm pump. The body is provided with a first outlet opening from the control chamber and the body has therein a first poppet valve including a first valve seat at the first outlet opening facing into a larger cross-section first poppet-valve chamber. A first poppet is positioned in the first poppet valve chamber and engages the first valve seat. A spring assembly is situated in the first poppet valve chamber for urging the first poppet against the first valve seat at a first predetermined force. An outlet opening from the first poppet-valve chamber is adapted to be connected to a sump for the working liquid.

Abstract: The float valve assembly is mounted in a liquid drain trap housing having an upper centrally located orifice and a lower centrally located outlet orifice and includes a float, an upper pin fixed to the top of the float and received in the upper orifice, a lower pin fixed to the bottom of the float in axial alignment with the upper pin and received in the lower orifice, a conical or semispherical valve seat at the lower end of the lower pin, and a mating valve seat-forming O ring clamped in the lower orifice. The upper and lower orifices are in axial alignment and form an alignment configuration for the float valve assembly by receiving therein the upper and lower pins and maintain them in generally vertical alignment. This ensures proper vertical seating and unseating of the conical or spherical valve seat on the O ring valve seat which is clamped within the lower orifice.