Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
259 words
Apparatus for sending information to a surface pressure pulse detector through drilling fluid in a borehole drilled in the earth with a drill bit on the lower end of a drill string in the borehole and through which the drilling fluid is circulated to flow through the interior of the drill string, past the drill bit, and into an annulus between the drill string and the borehole wall, the apparatus comprising: a retrievable assembly adapted to slide into and out of the drill string from the upper end of the drill string to a location near the drill bit, the assembly having a main bore with an inlet and an outlet through which a portion of the drilling fluid which flows through the drill string and past the drill bit may flow, the assembly being constructed and arranged so a first portion of the drilling fluid which flows through the drill string and past the drill bit may flow through the bore and a second portion of drilling fluid may flow through a substantially fixed flow cross sectional area between the assembly exterior and the drill string when the assembly is in the drill string; means for generating a control signal responsive to a downhole condition; and means responsive to the control signal to change the rate at which drilling fluid flows through the bore and without changing the effective cross sectional area for fluid flow between the assembly exterior and the drill string to send a pressure pulse through the drilling fluid to the surface pressure pulse detector.
Claim 2
Dependent Claim
259 words
Apparatus for sending information to a surface pressure pulse detector through drilling fluid in a borehole drilled in the earth with a drill bit on the lower end of a drill string in the borehole and through which the drilling fluid is circulated to flow through the interior of the drill string, past the drill bit, and into an annulus between the drill string and the borehole wall, the apparatus comprising: a retrievable assembly adapted to slide into and out of the drill string from the upper end of the drill string to a location near the drill bit, the assembly having a main bore with an inlet and an outlet through which a portion of the drilling fluid which flows through the drill string and past the drill bit may flow, the assembly being constructed and arranged so a first portion of the drilling fluid which flows through the drill string and past the drill bit may flow through the bore and a second portion of drilling fluid may flow through a substantially fixed flow cross sectional area between the assembly exterior and the drill string when the assembly is in the drill string; means for generating a control signal responsive to a downhole condition; and means responsive to the control signal to change the rate at which drilling fluid flows through the bore and without changing the effective cross sectional area for fluid flow between the assembly exterior and the drill string to send a pressure pulse through the drilling fluid to the surface pressure pulse detector.
Claim 3
Dependent Claim
31 words
Apparatus according to claim 1 in which the cross sectional area for fluid flow between the assembly exterior and the drill string is substantially greater than that of the assembly bore.
Claim 4
Dependent Claim
66 words
Apparatus according to claim 1 or 2 which includes means between the assembly bore inlet and outlet defining a flow restriction between the drill string interior and the assembly exterior to create a working pressure drop in the drilling fluid between the bore inlet and outlet, and means responsive to the pressure drop to change the rate at which drilling fluid flows through the assembly bore.
Claim 5
Dependent Claim
40 words
Apparatus according to claim 1 or 2 which includes latching means on the assembly to permit it to be retrieved from the drill string by a wire line from the surface without removing the drill string from the well bore.
Claim 6
Dependent Claim
24 words
Apparatus according to claim 4 in which the latching means is constructed and arranged to receive an overshot tool secured to a wire line.
Claim 7
Dependent Claim
23 words
Apparatus according to claim 1 or 2 which includes a valve for opening and closing the assembly bore in response to the signal.
Claim 8
Dependent Claim
33 words
Apparatus according to claim 1 which includes a main valve for changing drilling fluid flow rate through the bore, and a pilot valve responsive to the control signal for actuating the main valve.
Claim 9
Dependent Claim
25 words
Apparatus according to claim 7 in which the main valve is powered by the pressure drop in the drilling fluid flowing through the drill string.
Claim 10
Dependent Claim
17 words
Apparatus according to claim 7 or 8 which includes a rotary solenoid for operating the pilot valve.
Claim 11
Dependent Claim
27 words
Apparatus according to claim 7 or 8 in which the pilot valve is a spool valve, and which includes an electric motor for operating the spool valve.
Claim 12
Dependent Claim
12 words
Apparatus according to claim 10 in which the electric motor is reversible.
Claim 13
Dependent Claim
29 words
Apparatus according to claim 11 which includes stop means for limiting the travel of the electric motor when moving the spool valve between the open and the closed portions.
Claim 14
Dependent Claim
30 words
Apparatus according to claim 7 or 8 in which the pilot is opened and closed by linear movement of a valve plug, and a linear solenoid for moving the plug.
Claim 15
Dependent Claim
23 words
Apparatus according to claim 1 or 2 which includes an outwardly extending sleeve on the assembly between the main bore inlet and outlet.
Claim 16
Dependent Claim
14 words
Apparatus according to claim 14 in which the sleeve is removable from the assembly.
Claim 17
Dependent Claim
44 words
Apparatus according to claim 1 or 2 which includes a replaceable sleeve mounted in the drill string at a location between the assembly bore inlet and outlet when the assembly is positioned in the drill string to send pressure pulses through the drilling fluid.
Claim 18
Dependent Claim
40 words
Apparatus according to claim 16 in which the drill string is made up of a series of pipe sections threaded together at adjacent ends, and an outwardly extending flange on the sleeve clamped between two adjacent ends of pipe sections.
Claim 19
Dependent Claim
31 words
Apparatus according to claim 16 in which the sleeve includes an inwardly extending portion to create a flow restriction between the inlet and outlet of the main bore in the assembly.
Claim 20
Dependent Claim
17 words
Apparatus according to claim 1 or 2 which includes a replaceable interior sleeve in the assembly bore.