| 摘要 |
<p>An apparatus (1) for mixing first and second gases includes first and second valves (2, 3) each having a stem (14) the axial movement of which controls the flow of the gases through their respective valves. Each valve stem (14) has one end engaging a control surface (16) of a thrust plate (18) mounted for axial and pivotal movement on a shaft (20). Means including a plunger (26) is provided for pivoting the thrust (18) so that one valve stem (14) is moved axially relative to the other thereby increasing the rate of flow of one gas through its respective valve whilst concomitantly decreasing the rate of flow of the other gas through its respective valve to vary the relative proportion of the gases without varying the total flow rate. Total flow adjuster (34) bears on the plunger (26) for moving the thrust plate (18) axially towards and away from the valve stems (14) thereby to vary the total rate of flow of the gases without varying the relative proportions of each gas flowing through its respective valve. </p> |
