| 摘要 |
PURPOSE:To measure the specific gravity of an electrolyte accurately in a short time by surrounding a specific gravity sensor with a sulfuric acid-resisting filter to prevent the entrance of bubbles into a specific gravity measuring space. CONSTITUTION:Plates 4, 5 provided with leads 2, 3 are contained in an electrolyte container 1, and an electrolyte 6 comprising aqueous sulfuric acid solution is filled to form a lead-acid battery 7. The specific gravity of the electrolyte 6 is measured by inserting a floating hydrometer 8 or an ultrasonic hydrometer in the electrolyte 6 in the electrolyte container 1. When, the sensor of the hydrometer 8 is sorrounded with a sulfuric acid-resisting filter 9 made of a material such as high polyer fiber, for example polypropylene fiber, foamed metal, porous alumina, or sintered glass to prevent the entrance of babbles to a measuring space. The filter 9 is fixed to the electrolyte container 1 with a supporter. |
