US3724558A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for controlling the rotary speed of a drill
Assignee: Texaco Inc
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Filing: 1971-09-22
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Granted: 1973-04-03
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Expires: 1991-09-22
Abstract
Abstract The rotary speed of a rotary drive system, including a rotary engine, for a drill in a well is maintained at a predetermined value and is sensed by a tachometer. An electrical signal from the tachometer is converted to a pneumatic signal by an electropneumatic transducer which is applied to a receiver-controller receiving a supply of filtered air at a predetermined pressure. When the electrical signal from the tachometer changes due to a change in the rotary speed of the rotary drive system from the predetermined value, the pneumatic output from the receiver controller changes accordingly until the rotary speed of the rotary drive system is once again at the predetermined value. The pneumatic output from the receiver controller remains at the pressure which returned the rotary speed to its predetermined value. In achieving speed control, the pneumatic output from the receiver controller is effectively amplified by a booster relay receiving filtered air at a second predetermined pressure to provide a pneumatic signal. The pneumatic signal from the booster relay is applied to the throttle of the rotary engine to control the engine''s rotary speed and hence the rotary speed of the rotary drive system and drill.
Inventors
- 👤 H Rundell
- 👤 R Pittman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:07
CPC Classifications
E; E21; E21B; E21B44/00; Y; Y10; Y10T; Y10T137/00; Y10T137/0971; Y10T137/1007; Y10T137/1044
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
131 words
A system for maintaining the rotary speed of a drill, irrespective of changes in the earth''s formation, said drill being driven by a rotary drive system including a rotary engine, comprising means for sensing the rotary speed of the rotary drive system and providing an electrical signal representative thereof, a transducer connected to the sensing means for converting the electrical signal to a pneumatic signal, means connected to the transducer and receiving air at a predetermined pressure for providing a pneumatic control output in accordance with the pneumatic signal, and means connected to the output means and to the rotary engine for controlling the rotary engine in accordance with the pneumatic control output from the output means to maintain the rotary speed of the rotary drive system and of the drill.
Claim 2
Independent Claim
131 words
A system for maintaining the rotary speed of a drill, irrespective of changes in the earth''s formation, said drill being driven by a rotary drive system including a rotary engine, comprising means for sensing the rotary speed of the rotary drive system and providing an electrical signal representative thereof, a transducer connected to the sensing means for converting the electrical signal to a pneumatic signal, means connected to the transducer and receiving air at a predetermined pressure for providing a pneumatic control output in accordance with the pneumatic signal, and means connected to the output means and to the rotary engine for controlling the rotary engine in accordance with the pneumatic control output from the output means to maintain the rotary speed of the rotary drive system and of the drill.
Claim 3
Dependent Claim
53 words
A system as Described in claim 1 further comprising switching means connecting the control means to the rotary engine and receiving a supply of air at a pressure which may be manually adjusted for providing either the pneumatic control output or the received air to the rotary engine to control the rotary engine.
Claim 4
Dependent Claim
20 words
A system as described in claim 2 in which the switching means is manually operated to accomplish its switching function.
Claim 5
Dependent Claim
132 words
A system as described in claim 2 further comprising means for sensing the torque experienced by the rotary drive system and providing an electrical torque signal corresponding thereto, and means connected to the torque sensing and to the switching means for providing an electrical output to the switching means when the amplitude of the torque signal exceeds a predetermined value corresponding to a maximum permissable torque and no electrical output when the amplitude of the torque signal is equal to or less than the predetermined value; and in which the switching means provides the pneumatic control output from the output means to the rotary engine when the electrical output means provides no electrical output and provides the received air to the rotary engine when the electrical output means provides an electrical output.
Claim 6
Dependent Claim
22 words
A system as described in claim 4 in which the switching means may also be manually operated to accomplish its switching function.
Claim 7
Dependent Claim
59 words
A system as described in claim 4 in which the electrical output means continues to provide no output after the torque signal amplitude drops below the predetermined value until the electrical output means receives a reset signal, and manually operative means connected to the electrical output means for providing a reset signal to the electrical output means when operated.
Claim 8
Dependent Claim
91 words
A system as described in claim 6 in which the output means includes a receiver controller having a set point and receiving air at a predetermined pressure and connected to the transducer for providing air at a pressure controlled by a change in the pneumatic signal with respect to the position of the set point, and a booster relay connected to the receiver controller and receiving air at a second predetermined pressure for control output which is in effect an amplification of the pressure of the air from the receiver controller.
Claim 9
Independent Claim
98 words
A method for maintaining the rotary speed of a drill, irrespective of changes in the earth''s formation, being driven by a rotary drive system including a rotary engine, which comprises sensing the rotary speed of the rotary drive system, providing an electrical signal representative of the rotary speed of the rotary drive system, converting the electrical signal to a pneumatic signal, providing a pneumatic control output in accordance with the pneumatic signal, and controlling the rotary engine in accordance with the pneumatic control output to maintain the rotary speed of the rotary drive system and of the drill.
Claim 10
Independent Claim
98 words
A method for maintaining the rotary speed of a drill, irrespective of changes in the earth''s formation, being driven by a rotary drive system including a rotary engine, which comprises sensing the rotary speed of the rotary drive system, providing an electrical signal representative of the rotary speed of the rotary drive system, converting the electrical signal to a pneumatic signal, providing a pneumatic control output in accordance with the pneumatic signal, and controlling the rotary engine in accordance with the pneumatic control output to maintain the rotary speed of the rotary drive system and of the drill.
Claim 11
Dependent Claim
68 words
A method as described in claim 8 which further comprises providing a second pneumatic control output whose pressure does not correspond to the rotary speed of the rotary system and may be manually controlled, and in which the second mentioned providing step includes providing the second pneumatic control output, when desired, in lieu of the first pneumatic control output so that the rotary engine may be controlled manually.
Claim 12
Dependent Claim
125 words
A method as described in claim 9 which further comprises sensing the torque experienced by the rotary drive system, and providing an electrical torque signal corresponding to the sensed torque; and in which the second mentioned providing step includes providing the second pneumatic control signal in lieu of the first pneumatic control signal once the torque signal exceeds a predetermined value, corresponding to a maximum permissable torque, until a reset signal occurs and then providing the first pneumatic control output in lieu of the second pneumatic control output so as to prevent failure of the drill or the rotary drive system due to excEssive torque, and providing a reset signal when the first pneumatic control output may be safely used to control the rotary engine.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |