| 摘要 |
PURPOSE:To make it possible to check the airtightness of a cell before shipment by installing slits which reach the edge of a rubber sheet valve in the rubber sheet valve. CONSTITUTION:Four slits 5 which reach the edge of a rubber sheet valve 4 are installed in the rubber sheet valve 4 which is fitted to a vent plug of a middle cover 2. When the pressure in each cell is reduced by charge or discharge, recessed spherical surfaces 6 corresponding to vents 3 are produced in the rubber sheet valve 4 and tensile force is applied to the slits 5 to open them like slits 5'. For example, even if the pressure reducing rate in a cell 10 is faster than that in other cells and the recessed spherical surface in the valve is produced early than a central cell 9, slits 5 are opened like slits 5'. Therefore, the valve corresponding to the vent of the central cell is not pulled and the recessed spherical surface 6 is opened. |
