Reading of a variable liquid level inside a liquid transporter tank which has a transparent plaque on its upper part, uses a floating mirror sliding over a scale inside the tank to reflect scale reading through plaque

摘要

A graduated scale (7) is fitted inside the tank. A mirror (6) reflects an image of the liquid on the scale to the tanks exterior. The mirror is fitted to a slide (4) and carried on an annular float (5) that moves along the scale according to the liquid level. The mirror is counterbalanced by a weight (11). An electric lamp (9) illuminates the scale. The tank has on its upper part has a transparent plaque (2) positioned so that the scale can be read through it. The scale and mirror are mounted inside the tank (1) so that the mirror remains in a lower position when the liquid level falls below a predetermined level.