| 摘要 |
<p>A discrete device attachable to a rotary sprinkler head for varying the water pressure therein to constrain the water distribution to produce a desired irrigation pattern. The sprinkler head attachment-device includes a housing having an intermediate wall partitioning the housing into upper and lower water chambers with an orifice therebetween. A spindle having a cam rotatable with the sprinkler head is mounted within the upper chamber. A cam follower is pivoted into engagement with the cam by means of hydraulic pressure. A valve key portion of the cam follower constricts the flow of water through the orifice in a variable manner controlled by the shape of the cam whereby the desired spray pattern is achieved.</p> |
