| 摘要 |
A gas meter has measuring chambers each having a flexible diaphragm free to reciprocate and in so doing to operate valves admitting gas to the chambers. The drive from the diaphragms to the valves includes an adjustable crank assembly. Crank arms (25, 26) are secured by a resilient pin (27) spring fitted to one of a number of bores (30) in a tangent member (28), rotatable on a spindle (31). A worm wheel (33) mounted on tangent member (28) drives a rack member (23) secured to the spindle. Rotation of the worm wheel rotates the tangent member with respect to the spindle and so adjusts the phase relationship between the diaphragm and the valves. The bores (30) are at different radii allowing the throw of the crank arms to be varied. |
