Diaphragm gas meter uses electronic measurement system

摘要

PROBLEM TO BE SOLVED: To provide a gas meter having a structure in which rear pipes cause no obstacles when the occurrence of dew condensation and the entry of rainfall are prevented and a gas meter is installed.SOLUTION: A control chamber 4 is formed on the front side of an upper case 2 of a gas meter body 1. An atmosphere introducing structure is formed between mutual joining edge parts of the cover 5 which covers the control chamber 4 and a front of this control chamber 4, and is composed of an atmosphere introducing port 7 opened to the atmosphere and a ventilation path 6 continued thereto and a ventilation port opened to the control chamber 4. The ventilation path 6 is attached with a ventilation filter 10. In the ventilation path 6, a barrier is formed in the space from the atmosphere introducing port 7 to the ventilation. The ventilation path 6 formed with this barrier is provided with a buffer 9 for the purpose of absorbing an abrupt fluctuation of a ventilation pressure by expanding a part of the ventilation path. The ventilation filter 10 is formed with a ventilation slit 11. A width of this ventilation slit 11 is set to 0.20 mm or less. In addition, a rear lid which becomes a cause of creating a protruding part from a rear part of the control chamber 4 is eliminated so as not to become the obstacle to the pipes.