06840493 is referenced by 10 patents and cites 14 patents.

A valve actuator is provided in which a complementary set of pinions, each driven by a pair of racks, are located on opposite sides of the valve to be actuated. The racks are part of an annular bearing assembly and are coupled to one another through a hydraulic cylinder or some other displacement device. A pinion retaining sleeve is provided to shield the racks and pinions and prevents parts of the valve actuator from being thrown in operation. The piston retaining sleeve may include a maintenance aperture for installing or repairing a pinion and a second aperture for viewing the rotation of the pinion. The bearing assemblies each include a bearing housing and a bearing retainer that cooperate to shield the bearing assembly.

Title
Valve actuator
Application Number
10/114822
Publication Number
6840493 (B2)
Application Date
April 3, 2002
Publication Date
January 11, 2005
Inventor
Beat Kuttel
Spring, 77382
TX, US
Allan S Richardson
Spring, 77382
TX, US
Lemuel T York
Montgomery, 77356
TX, US
Agent
Baker Botts L
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