| 摘要 |
<p>An object launching apparatus for a well has a housing, a flow mandrel, and a cage. The flow mandrel is disposed in the housing's internal chamber, and a flow passage in the mandrel communicates flow from the housing's inlet to the mandrel's flow port, which in turn communicates with the housing's outlet. The cage is disposed in the internal chamber and defines pockets for holding the objects. A motor and shaft move the cage in the housing relative to the mandrel's flow port so the cage's pockets can be selectively positioned in communication between the mandrel's flow port and the housing's outlet. This allows any of the object(s) held in the positioned pocket to be launched into the flow to the well. Preferably, the motor rotates the shaft so the cage can ride linearly along the shaft's thread and the cage can rotate through a cammed engagement with the housing.</p> |
