Alan Martyn Eddison: Downhole tool. Andergauge, Alston & Bird, January 30, 2007: US07168493 (38 worldwide citation)

A hydraulic tool assembly for a downhole tool comprises a body (12), first and second members (14, 16) mounted for independent movement with respect to the body, and first and second control fluid chambers (24, 26) associated with the respective first and second members. Movement of the first member ...

Alan Martyn Eddison: Drilling method and measurement-while-drilling apparatus and shock tool. Andergauge, Alston & Bird, July 8, 2003: US06588518 (35 worldwide citation)

A downhole drilling method comprises producing pressure pulses in drilling fluid using measurement-while-drilling (MWD) apparatus (

Eddison Alan Martyn: Eccentrically weighted drilling apparatus for deviated boreholes. Andergauge, May 10, 2000: GB2343470-A (22 worldwide citation)

A directional drilling apparatus (10) has an eccentric mass (20) rotatably mounted on a mandrel (18). The mandrel is coupled to a drill string (12) and a bit (24) can be offset in the borehole by an offset portion (22). There is also a flexible string section (14) forming a flex joint for coupling t ...

Alan Martyn Eddison: Directional drilling apparatus. Andergauge, Alston & Bird, March 21, 2006: US07013994 (20 worldwide citation)

Directional drilling apparatus for use in drilling a deviated bore comprises a mandrel for mounting to a drill string and having a main axis. A non-rotating mass is rotatably mounted on the mandrel and has a center-of-gravity spaced from the mandrel axis. The apparatus further comprises an offsettin ...

Alan Martyn Eddison, Mark Adam: Downhole tool having radially extendable members. Andergauge, Alston & Bird, April 27, 2010: US07703553 (18 worldwide citation)

A downhole tool comprises a body, radially extendable members mounted to the body and movable between retracted and extended positions, a cam member operatively associated with the extendable members and movable relative to the body to extend the extendable members, and a support member configurable ...

Anderson Charles Abernethy C O: Tool actuator.. Andergauge, January 23, 1991: EP0409446-A1 (18 worldwide citation)

A tool actuator which comprises a casing (8) containing a pipe (1), which is movable from a locking position to an unlocking position, under the action of a fluid pumped through the casing. When the pipe is in the locking position it locks a mandrel (4) in an activating or deactivating position. Whe ...