Stroke actuated well testing tool

A tubing string supported well testing tool, comprising:

• a. a tubular structure having a series of control subassemblies, each having components capable of limited relative axial movement;
• b. a tubular packer suspended from the tubular structure and adapted to be set in a well core;
• c. a first of the control subassemblies having radially directed ports, said ports occupying an open position during movement of the tubular structure and packer through the well bore to permit passage of well fluid through the packer into the region surrounding the tubing string, said ports occupying closed positions when the packer is set in the well bore;
• d. a rotatable main valve within the tubular structure;
• e. a second of the control subassemblies for moving the valve successively between a position closing flow through the tubular structure and a position permitting flow through the packer and tubular structure;
• f. said second control assembly including a driven gear carried by the main valve, an annular gear carried within the walls of the tubular structure, a multiple cam cylinder having a drive gear engagable with the the driven gear, longitudinally and circumferentially extending cam elements, and longitudinally movable cam driving elements for turning the cam cylinder to effect rotation of the main valve;
• g. and a pressure counterbalancing means, operable when the main valve is closed and the well pressure below the main valve exceeds the pressure above, for applying a counter-force to facilitate movement of the main valve to its open position.