Patent ID: 7201231

Claim:
Apparatus for remotely activating an activatable tool in a wellbore, the apparatus comprising: a positive displacement pump for causing circulation of a fluid under pressure in the a control device for controlling the speed of operation of the pump; a conduit that is operatively connected to the pump and extends into the wellbore for conveying the fluid thereinto on operation of the pump; a downhole transducer, that is capable of detecting changes in the pressure of the fluid and generating one or more detected pressure signals indicative thereof; a processor that is capable of generating one or more actuator commands in dependence on the detected pressure signals generated by the downhole transducer; one or more actuators that are each operable to activate at least a part of the activatable tool in dependence on a said actuator command; an activatable tool at a downhole location; a modulating valve for modulating the pressure of fluid in the conduit; and a remote transducer that is operatively connected to detect pressure of the fluid in the conduit at a location remote from the downhole transducer, wherein operation of the modulating valve is dependent on a downhole event, wherein the control device is operable to cause the pump to generate one or more digital acoustic signals having waveforms, in the fluid, the waveforms being detectable by the downhole transducer; and wherein the modulating valve is operable to generate one or more analogue acoustic signals, in the fluid, that are detectable by the remote transducer; wherein the conduit is a drillpipe that is moveable within the wellbore; wherein the activatable tool is moveable relative to the drillpipe; and wherein the drillpipe and the activatable tool include mutually engageable latch parts that, when mutually engaged, retain at least a part of the activatable tool in a retracted position relative to the downhole end of the drillpipe and when disengaged permit movement of the activatable tool to an advanced position in which at least part of the activatable tool protrudes from the downhole end of the drillpipe, the apparatus including a release tool activator that is operable to cause disengagement of the latch parts from one another.