摘要 |
<p>An actuating device operated by a pressure medium, such as compressed air, acting within a housing, can be secured to a valve by a mounting member attached to the valve. The actuating device includes a first piston guided in a cylinder part positioned on one side of the center part of the housing. A toothed rack is attached to the first piston and is in meshed engagement with a pinion shaft located within the center part of the housing. The pinion shaft is connected by a coupling part to the valve shaft. The same actuating device can be used for a larger valve by placing a second piston in another cylinder part on the opposite side of the center part from the first piston with a toothed rack attached to the second piston and in meshed engagement with the pinion shaft. The first and second pistons act in opposite directions and double the torque acting on the pinion shaft as compared to the torque delivered by the first piston.</p> |