Subsurface control apparatus for use in oil and gas wells

Claim 2

Subsurface control apparatus in accordance with claim 1 further including; a nonelectrical wire line connected to said housing means for supporting same in the pipe string; said wire line constituting the sole support means for said housing means and said means therewith.

Claim 3

Subsurface control apparatus in accordance with claim 1 wherein the magnetic detector means produces an electrical signal having a positive and a negative fluctuation each time the detector means moves past a pipe joint, the order of occurrence of the positive and negative fluctuations being dependent on the direction of movement of the detector means past the pipe joint, and wherein the electronic logic circuit means includes: bistable circuit means coupled to the magnetic detector means for changing states in response to the magnetic detector signals, the final state following any given magnetic detector signal depending on the order of occurrence of the positive and negative fluctuations; pulse generator circuit means coupled to the bistable circuit means for generating a delayed pulse a predetermined time interval after each change of state of a particular polarity in such bistable circuit means; an up-down pulse counter; circuit means for coupling the bistable circuit means to the up-down pulse counter for controlling the diRection of counting therein; circuit means for coupling the output of the pulse generator circuit means to the pulse counting input of the up-down pulse counter; timer circuit means for producing the control signal to be supplied to the downhole device a predetermined time interval after an activating signal is supplied to such timer circuit means; and logic circuit means coupled to the up-down pulse counter for detecting the occurrence of a predetermined number of downward counts and thereafter a predetermined number of upward counts for thereupon supplying an activating signal to the timer circuit means, such logic circuit means also including means for thereafter disabling the timer circuit means if more than predetermined numbers of net upward or downward counts occur after the activating signal is first supplied to the timer circuit means.

Claim 4

Subsurface control apparatus in accordance with claim 4 wherein the magnetic detector means includes: permanent magnet means for producing magnetic flux; pole piece means for enabling the magnetic flux to link with the well pipe; and coil means responsive to changes in the magnetic flux for producing electrical signals indicative of such changes.

Claim 5

Subsurface control apparatus in accordance with claim 1 wherein the electronic logic circuit means includes: counting circuit means for counting magnetic detector signals produced during downward and upward movements of the detector means; and circuit means coupled to the counting circuit means and responsive to the downward and upward counts of such counting circuit means for producing the control signal for the downhole device after the detection of a predetermined pattern of downward and upward counts.

Claim 6

Subsurface control apparatus in accordance with claim 6 wherein: the signals produced by the magnetic detector means have a polarity characteristic which is dependent on the direction of movement of the detector means past the pipe joint; and the counting circuit means includes up-down counter circuit means for counting in one direction in response to downward movement produced magnetic detector signals and for counting in the other direction in response to upward movement produced magnetic detector signals.

Claim 7

Subsurface control apparatus in accordance with claim 7 wherein the electronic logic circuit means further includes circuit means responsive to the magnetic detector signals for supplying pulses to the counting input of the up-down counter circuit means and for supplying direction control signals to the up-down counter circuit means for controlling the direction of counting for the pulses.

Claim 8

Subsurface control apparatus in accordance with claim 6 wherein the circuit means coupled to the counting circuit means includes: detector circuit means for producing an activating signal upon the detection of a predetermined pattern of downward and upward counts; and timer circuit means responsive to the activating signal for producing the control signal for the downhole device a predetermined time interval after the initial occurrence of the activating signal.

Claim 9

Subsurface control apparatus in accordance with claim 9 wherein the duration of the predetermined time interval of the timer circuit means is in the range of 10 to 30 minutes.

Claim 10

Subsurface control apparatus in accordance with claim 9 wherein the detector circuit means further includes means for disabling the timer circuit means if more than predetermined numbers of net upward or downward counts occur after the initial occurrence of the activating signal.