| 摘要 |
<p>An apparatus for retarding rotation of a nozzle includes a hollow housing, a rotary shaft within the housing, a rotatable rotor on the rotary shaft free to move axially along the shaft, and a cam assembly coupling the rotor and shaft together in the housing such that rotor rotation on the shaft causes the cam assembly to displace the rotor axially on the shaft in a first direction. A set of springs on the shaft biases the rotor in a second direction opposite the first direction on the shaft. Finally, a viscous fluid disposed between the rotor and the housing generates a drag on rotor rotation with the shaft. Relative rotation of the rotor with respect to the shaft in conjunction with a variable gap between the rotor and housing are used to slow and thus control rotary nozzle speed.</p> |
