Bellows-type gas meter

Abstract

A bellows-type gas meter comprises two compartments each having a diaphragm as well as a shaft common to said two compartments, said shaft having two eccentric cam assemblies, one of said eccentric cam assemblies being connected with the crank assemblies of said diaphragms and the other one of said eccentric cam assemblies being connected with the crank assemblies of two valves creating in a cyclic mode passages between the four chambers into which said two compartments are divided by said diaphragms and a gas inlet or a gas outlet respectively, said two eccentric cam assemblies being displaced relative to each other by an angle so that each such valve, during the chamber filling cycle, closes before the diaphragm operating in conjunction therewith moves into its final position, the eccentric cam assembly connected with said valves being provided with a disk cam assembly for each such valve, said disk cam assemblies being accommodated on said common shaft, the form of each such disk cam engaging with a substantially longitudinal opening of the crank assembly for the valve operated thereby not being circular so that the opening mode of each such valve is in a relationship with the diaphragm mode of motion, thereby keeping the error of the bellows-type meter small.