| 摘要 |
A standardized pressure instrument has one cylinder (12) through the upper opening of which a piston (14) is guided with minimum friction. An exact pressure is transmitted from a pressure chamber (30) formed between the inner front face of the piston and the base of the cylinder via a pipe (48). The pressure is determined by exerting precisely-defined forces on the piston, in particular by applying calibrated weights (46). By introduction or withdrawal of fluid through the pipe, the piston is maintained at a precise constant height by means of a regulating device (70) even under fluctuating loads on the piston. |
