Flexible-wall fuel pump with means to dampen wall oscillations

Claim 1

A fuel pump self-compensated for changes in fuel head pressure for use with two stroke cycle engines comprising in combination: (a) a relatively rigid shell-like body member, (b) a resiliently expansible diaphragm disposed within said body member wherein said diaphragm defines a spacial confine which is variably expandable and contractable responsively to differential fluid pressure acting thereon, (c) first check valve means porting said confine defined by said diaphragm, (d) second check valve means porting said confine defined by said diaphragm, (e) a volume confined by said body member and interspaced between a preponderant portion of said diaphragm and said body member, (f) mechanical damper means adjustably retained by said body member for being set to project fixedly through varying distances into said volume to contact said diaphragm and produce deflection therein proportionate to the amplitude through which said spacial confine is variably driven in expansion by said fluid pressure differential, thereby to dampen expansion and contraction oscillations of said spacial confine, (g) an opening provided in said body member for communicating said volume with the environment of the crankshaft of an engine to which said fuel pump may be attached for use, thereby to provide pulsated drive operation of said diaphragm.