Patent US4248324A successfully refreshed from Google Patents.
US4248324A
Expired / Lapsed
US
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Seismic vibrator and method for improving the output of a seismic vibrator
Assignee: ExxonMobil Upstream Research Co
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Filing: 1979-02-07
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Granted: 1981-02-03
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Expires: 1999-02-07
Abstract
Abstract A method and apparatus for improving the power output of a seismic vibrator are provided. Compliant elements with variable stiffnesses are interposed between and connected to the holddown mass and the baseplate. When the compliant elements have a first stiffness, the vibrator-earth system has a first resonant frequency. When the compliant elements have a second stiffness, the vibrator-earth system has a second resonant frequency. During sweep, the compliant elements are set on the first stiffness until the vibrator has passed through the first resonant frequency; then the compliant elements are changed to their second stiffness and the sweep continues through the second resonant frequency.
Inventors
- 👤 Joseph F. Mifsud
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 20:11
CPC Classifications
G; G01; G01V; G01V1/00; G01V1/02; G01V1/143; G01V1/145; Y; Y10; Y10S; Y10S181/00; Y10S181/40; Y10S181/401
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
121 words
An apparatus for controlling the vibrations of a seismic vibrator having a holddown mass and a baseplate, said apparatus comprising: at least one compliant element connected to the holddown mass and to the baseplate, said compliant element having a variable stiffness; control means connected to the compliant element for varying the stiffness of the compliant element, said control means being responsive to an input signal; at least one sensor for measuring the frequency of the baseplate vibrations, said sensor generating a signal indicative of said frequency; and means for transmitting the sensor signal to the control means, whereby the stiffness of the compliant element between the holddown mass and the baseplate is controlled according to the frequency of the baseplate vibrations.
Claim 2
Independent Claim
121 words
An apparatus for controlling the vibrations of a seismic vibrator having a holddown mass and a baseplate, said apparatus comprising: at least one compliant element connected to the holddown mass and to the baseplate, said compliant element having a variable stiffness; control means connected to the compliant element for varying the stiffness of the compliant element, said control means being responsive to an input signal; at least one sensor for measuring the frequency of the baseplate vibrations, said sensor generating a signal indicative of said frequency; and means for transmitting the sensor signal to the control means, whereby the stiffness of the compliant element between the holddown mass and the baseplate is controlled according to the frequency of the baseplate vibrations.
Claim 3
Dependent Claim
16 words
The apparatus of claim 1, wherein said sensor measures the displacement of the baseplate from equilibrium.
Claim 4
Dependent Claim
14 words
The apparatus of claim 1, wherein said sensor measures the velocity of the baseplate.
Claim 5
Dependent Claim
11 words
The apparatus of claim 1, wherein said sensor is an accelerometer.
Claim 6
Dependent Claim
33 words
The apparatus of claim 1, wherein said compliant element comprises a hydraulic cylinder and a piston slideably disposed within said cylinder and defining within said cylinder two chambers, said chambers containing hydraulic fluid.
Claim 7
Dependent Claim
45 words
The apparatus of claim 5, wherein said control means comprises: a conduit communicating between said chambers to allow hydraulic fluid to flow between the chambers; and a valve disposed in said conduit, the position of said valve being responsive to the signal from the sensor.
Claim 8
Independent Claim
120 words
An apparatus for controlling the vibrations of a seismic vibrator, said vibrator having a holddown mass, a baseplate, and a driver for vibrating the baseplate, said driver being controlled by an electric sweep signal, said apparatus comprising: at least one compliant element connected to the holddown mass and to the baseplate, said compliant element having a variable stiffness; control means connected to the compliant element for varying the stiffness of the compliant element, said control means being responsive to an electric signal; and means for transmitting said electric sweep signal to said control means, whereby the stiffness of the compliant connection between the holddown mass and the baseplate is controlled by the electric sweep signal which also controls the driver.
Claim 9
Independent Claim
120 words
An apparatus for controlling the vibrations of a seismic vibrator, said vibrator having a holddown mass, a baseplate, and a driver for vibrating the baseplate, said driver being controlled by an electric sweep signal, said apparatus comprising: at least one compliant element connected to the holddown mass and to the baseplate, said compliant element having a variable stiffness; control means connected to the compliant element for varying the stiffness of the compliant element, said control means being responsive to an electric signal; and means for transmitting said electric sweep signal to said control means, whereby the stiffness of the compliant connection between the holddown mass and the baseplate is controlled by the electric sweep signal which also controls the driver.
Claim 10
Dependent Claim
33 words
The apparatus of claim 7, wherein said compliant element comprises a hydraulic cylinder and a piston slideably disposed within said cylinder and defining within said cylinder two chambers, said chambers containing hydraulic fluid.
Claim 11
Dependent Claim
44 words
The apparatus of claim 8, wherein said control means comprises: a conduit communicating between said chambers to allow hydraulic fluid to flow between the chambers; and a valve disposed in said conduit, the position of said valve being responsive to said electric input signal.
Claim 12
Dependent Claim
225 words
A seismic vibrator, said vibrator comprising in combination: a baseplate adapted to be coupled to the earth; a holddown mass connected to the baseplate so as to exert on the baseplate a holddown force which tends to keep the baseplate in contact with the earth; a reaction mass connected to the baseplate to permit reciprocation of the reaction mass with respect to the baseplate; a driver connected to the reaction mass for reciprocating the reaction mass with respect to the baseplate in order to vibrate the baseplate, said driver being responsive to electric signals; an electric source which generates an electric sweep signal to control said driver; a first conductor connected to the electric source and to the driver for transmitting said sweep signal from said electric source to said driver; at least one compliant element connected to the holddown mass and to the baseplate, said compliant element having a variable stiffness; control means connected to the compliant element for varying the stiffness of the compliant element, said control means being responsive to an electric input signal; a second conductor connected to the electric source and to the control means for transmitting said electric sweep signal to the control means, whereby the stiffness of the compliant connection between the holddown mass and the baseplate is controlled by the sweep signal which also controls the driver.
Claim 13
Dependent Claim
225 words
A seismic vibrator, said vibrator comprising in combination: a baseplate adapted to be coupled to the earth; a holddown mass connected to the baseplate so as to exert on the baseplate a holddown force which tends to keep the baseplate in contact with the earth; a reaction mass connected to the baseplate to permit reciprocation of the reaction mass with respect to the baseplate; a driver connected to the reaction mass for reciprocating the reaction mass with respect to the baseplate in order to vibrate the baseplate, said driver being responsive to electric signals; an electric source which generates an electric sweep signal to control said driver; a first conductor connected to the electric source and to the driver for transmitting said sweep signal from said electric source to said driver; at least one compliant element connected to the holddown mass and to the baseplate, said compliant element having a variable stiffness; control means connected to the compliant element for varying the stiffness of the compliant element, said control means being responsive to an electric input signal; a second conductor connected to the electric source and to the control means for transmitting said electric sweep signal to the control means, whereby the stiffness of the compliant connection between the holddown mass and the baseplate is controlled by the sweep signal which also controls the driver.
Claim 14
Dependent Claim
49 words
The vibrator of claim 10, wherein said compliant element comprises: a hydraulic cylinder connected to said holddown mass; a piston slideably disposed within said cylinder and defining within said cylinder two chambers, said chambers containing hydraulic fluid, and a piston rod connected to said piston and to the baseplate.
Claim 15
Dependent Claim
46 words
The vibrator of claim 11, wherein said control means comprises: a conduit communicating between said chambers to allow hydraulic fluid to flow between the chambers; and a valve disposed in said conduit, the position of said valve being responsive to the frequency of said input signal.
Claim 16
Dependent Claim
49 words
The vibrator of claim 10, wherein said compliant element comprises: a hydraulic cylinder connected to said baseplate; a piston slideably disposed within said cylinder and defining within said cylinder two chambers, said chambers containing hydraulic fluid; and a piston rod connected to said piston and to the holddown mass.
Claim 17
Dependent Claim
46 words
The vibrator of claim 13, wherein said control means comprises: a conduit communicating between said chambers to allow hydraulic fluid to flow between the chambers; and a valve disposed in said conduit, the position of said valve being responsive to the frequency of said input signal.
Claim 18
Dependent Claim
25 words
The vibrator of claim 10, wherein said control means changes the stiffness of said compliant element when the sweep signal passes through a preselected frequency.
References Cited (Backward Citations)
US2910134A
Cited
US3106982A
Cited
US3282372A
Cited
US3363720A
Cited
US3578102A
Cited
US3840090A
Cited
US3884324A
Cited
US3929206A
Cited
US4014403A
Cited
US4147228A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-02-03 | 1984-08-04 | 1985-02-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-03 | 1988-08-04 | 1989-02-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-03 | 1992-08-04 | 1993-02-03 | $7700.00 | Window Closed / Lapsed |