| 摘要 |
A peak flow meter is provided which comprises an elongated body (22) having a longitudinal direction and a predetermined cross sectional shape and a growing area. The body (22) has an open entering end (24) and an open exit end (26). The body (22) is circumferentially continuous substantially from end to end. A piston (52) and an indicator (68) are mounted in said body (22) for movement longitudinally thereof upon exhalation into the open entering end (24). The indicator (68) is pushed along said body (22) for movement by the piston (52) longitudinally of said body (22). The indicator (68) is of low mass so as not to overshoot, and is returned to rest by shaking a weight (82) against it. A logarithmic scale is provided along said body (22) against which the position of said indicator (68) can be read. <IMAGE> |
