| 摘要 |
<p>Awatertimer (10) including a housing (12) having an inlet (14) and outlet (16) through which water flows to drive an impeller (20) and speed reducer (22) used to determine the open time of a valve member (18). The valve member (18) is movable In one direction, corresponding with one direction of axial movement of the timer dial (26), into a water flow position out of engagement with a valve seat (50) and movable in an opposite direction, corresponding with an opposite direction of axial movement of the dial (26), into engagement with the valve seat (50) into a water shut-off position. A biasing arrangement (30) including the relative sizes of first and second pressure responsive surface areas (72,75) of the valve member (18) functions to bias the same into its water shut-off position when the dial (26) is in its water shut-off position and a source of water under pressure is communicated with the inlet (14). The biasing arrangement (30) is changed in response to the axial movement of the dial (26) in the one direction into its water flow position, the change being sufficient to bias the valve member (18) from its water shut-off to its water flow position.</p> |
