Patent ID: 8925257
Filing Date: 2015-01-06
Classification: E21B

Abstract:
1. An apparatus comprising: a platform comprising a platform floor with an opening therein; a carriage support comprising a lower portion attached to the platform and an opposing, upper portion, wherein the carriage support is located proximate the opening; and a drive carriage adapted to be attached to the carriage support, wherein the drive carriage comprises: a first mast section located below the platform floor, the first mast section extending alone a first axis, the first mast section having a longitudinal edge with teeth located thereon, being adapted to travel along the first axis upon activation of the plurality of motors, and being adapted to attach to and detach from the platform, wherein each pinion of the plurality of pinions is adapted to engage the teeth of the first mast section and to operably couple the drive carriage to the first mast section, wherein activation of the plurality of motors effects relative movement between the first mast section and the drive carriage along the first axis; and wherein the first mast section and the drive carriage are located below the platform floor and the opening, wherein the drive carriage is adapted to travel along the first axis towards the platform floor upon activation of the plurality of motors and towards the upper portion of the carriage support, wherein an upper portion of the drive carriage is adapted to be attached to and detach from the lower portion of the carriage support, and to be attached to the upper portion of the carriage support.