Leakge-proof and shock-proof equalising valve for gas

The utility model relates to a leakge-proof and shock-proof equalising valve for gas, comprising a valve shell. A pressure regulating device is arranged at the gas inlet inside the valve shell. An elastic ball valve is arranged at the low pressure gas outlet inside the valve shell. Besides, a vent button device is arranged on the valve shell. The elastic ball valve comprises a valve cavity, and the valve cavity is provided with a porthole which is communicated with the gas inlet, the low pressure gas outlet and the vent button device. The cross section of the cavity body of the valve cavity takes a big upper end a small lower end. The valve cavity is internally provided with a valve body which can close the channel of the valve cavity communicated with the low pressure gas outlet. The valve body is arranged on a valve seat, with a certain distance from the porthole which is communicated with the lower pressure outlet. The valve seat is connected with the valve cavity through a movable supporting device, and the barycenter of the movable supporting device is unstable. As the utility model is provided with a cavity with a cross section changing from big to small and an elastic ball valve which is supported by the movable supporting device with an unstable barycenter, the equalizing valve has the advantages of automatically closing gas source under extremely small gas leakage and sensate earthquake, thereby completely avoiding danger and tragedy.