Patent ID: 8631949

Claim:
A tubulars storage device for storing a plurality of tubulars, said tubulars storage device comprising: a slot having an opening at a front end thereof, said slot forming a path of displacement for tubulars allowing to place tubulars at respective storage positions distributed along the slot and/or removal of said tubulars from the slot, a rotary latch members shaft, which is mounted substantially parallel to the slot, a drive connected to the rotary latch members shaft, said drive being adapted to effect controlled angular rotation of the latch members shaft, a plurality of latch members which are mounted on the latch members shaft so as to rotate with the latch members shaft and are arranged at spaced apart locations along the latch members shaft, wherein said plurality of latch members include a front latch member having a smallest angular extension and a rear latch member having a largest angular extension as well as one or more intermediate latch members between said front and rear latch member, each of said intermediate latch members having a greater angular extension than the preceding latch member on the latch members shaft, wherein the drive is adapted to selectively bring the rotary latch members shaft in one of a number of distinct angular positions, said number corresponding to the number of latch members on the latch members shaft plus one, and wherein the angular extension of each of the latch members on the latch members shaft is chosen such that: in a first angular position of the rotary latch members shaft all latch members on the shaft extend in the path of displacement of tubulars, thereby prohibiting displacement of the tubulars along the slot, in a second angular position only the front latch member is located out of said path of displacement thereby effectively unlocking the front latch member and allowing the passage of a tubular, in each subsequent angular position said front latch member remains located out of said path of displacement of the tubulars, and thus effectively unlocked, and a successive latch member is also located out of said path of displacement, and thus effectively unlocked, and in a final angular position of the shaft all latch members are located out of the path of displacement of the tubulars and thus effectively unlocked.