1. Seismic source comprising an actuator having a rotary part and a reciprocative part, conversion means to convert a rotation of the rotary part into a reciprocal movement of the reciprocative part, and a vibrator body that is connected to the reciprocative part of the actuator by means of a spring, wherein the conversion means comprises mechanical interaction means arranged to mechanically convert the rotation of the rotary part to the reciprocal movement of the reciprocative part, and wherein the mechanical interaction means comprises first and second corrugated coupling surfaces provided on the rotary part and the reciprocative part, which first and second coupling surfaces are slidably arranged with respect to each other.
2. The seismic source of claim 1, wherein the rotary part and the reciprocative part are frequency-coupled.
3. The seismic source of claim 1, wherein injection means is provided for injecting a functional fluid between the first and second corrugated coupling surfaces.
4. The seismic source of claim 3, wherein the injection means is arranged for injecting the functional fluid in the vicinity of a centre of rotation of the rotary part.
5. The seismic source of claim 3, wherein the injection means comprises a functional fluid recycling loop, arranged to suck up functional fluid after it has been injected, and to re-inject the sucked up functional fluid in the vicinity of the centre of rotation.
6. The seismic source of claim 5, wherein the recycling loop is driven by a pressure difference resulting from centrifugal work exercised on the functional fluid due to the rotation of the rotary part.
7. The seismic source of claim 1, wherein the first and second corrugated coupling surfaces have mutually different corrugation profiles.
8. The seismic source of claim 1, wherein the rotary part is supported by bearing means, the bearing means preferably comprising first and second diamond-comprising surface layers being slidably engaged with each other, and wherein the bearing means are located in the recycling loop.
9. The seismic source of claim 1, wherein the spring has a stiffness sufficiently high to ensure a sliding engagement between the corrugated coupling surfaces.
10. The seismic source of claim 1, further comprising adjustment means for varying the stiffness of the spring.
11. The seismic source of claim 1, adapted for use in a sub surface bore hole.
12. The seismic source of claim 11, wherein the vibrator body is arranged to engage in contact with the bore hole.
13. The seismic source of claim 1, wherein the conversion means is capable of converting the rotation of the rotary part into the reciprocal movement of the reciprocative part having a reciprocation frequency of higher than 9 Hz.
14. The seismic source of claim 1, further comprising drive means for rotating the rotary part.
15. The seismic source of claim 14, wherein the drive means comprises a hydraulic motor.
16. The seismic source of claim 1, wherein the conversion means is capable of converting the rotation of the rotary part into the reciprocal movement of the reciprocative part having a reciprocation frequency of higher than 90 Hz.
17. The seismic source of claim 1, wherein the conversion means is capable of converting the rotation of the rotary part into the reciprocal movement of the reciprocative part having a reciprocation frequency of higher than 0.9 kHz.
18. The seismic source of claim 1, wherein the seismic source is adapted for use in a borehole formed in an earth formation and wherein in use the vibrator body is pressed against a wall of the borehole.
19. The seismic source of claim 18, wherein the spring transmits the reciprocal movement of the reciprocative part into an oscillatory actuated force onto the formation.
20. Seismic source comprising an actuator having a rotary part and a reciprocative part, conversion means to convert a rotation of the rotary part into a reciprocal movement of the reciprocative part, a vibrator body that is connected to the reciprocative part of the actuator by means of a spring, and adjustment means for varying the stiffness of the spring, wherein the adjustment means is controllable in response to a reciprocation frequency of the reciprocative part.
21. The seismic source of claim 1, wherein the spring comprises a pressure chamber filled with a liquid, whereby relative movement of the reciprocative part with respect to the vibrator body causes compression or decompression of the liquid.
22. The seismic source of claim 21, wherein the pressure chamber is connected to a high-pressure outlet of a liquid pump for controlling a base liquid pressure inside the pressure chamber.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method of deploying an endograft comprising the steps of:
delivering an endograft to a diseased portion of a body lumen, said endograft being radially constrained by a sheath and select longitudinal portions of said endograft being radially constrained by releasable restraining members operatively associated with said select longitudinal portions of said endograft;
withdrawing said sheath to partially deploy said endograft, wherein said releasable restraining members constrain said selected longitudinal portions of said endograft to provide a flow path external said endograft proximate said restraining members while permitting portions of said endograft intermediate said selected longitudinal portions to expand;
releasing said restraining members to further deploy said select longitudinal portions to fully expand said endograft.
2. The method of claim 1 further comprising, prior to the step of releasing said restraining members, the steps of:
determining the position of said endograft; and
repositioning said endograft, as required.
3. The method of claim 2 wherein the position of said endograft is determined using radiography.
4. The method of claim 1 wherein said restraining members are released selectively.
5. The method of claim 4 wherein said restraining members are released sequentially.
6. The method of claim 1 wherein said step of releasing said restraining members comprises severing said restraining members and withdrawing them distally.
7. The method of claim 1 wherein said restraining members are flexible tubes extending longitudinally over said endograft in threaded engagement proximal to said endograft, and said step of releasing said restraining members comprises unscrewing said flexible tubes and withdrawing said flexible tubes distally over said endograft.
8. An endograft delivery system comprising:
a catheter configured to carry said endograft and to be endoluminally advanced through a body lumen;
a nosecone attached to a proximal end of said catheter;
a sheath configured to constrain said endograft in a radially compressed configuration during endoluminal advancement and to be axially withdrawn from said endograft to partially deploy said endograft; and
at least two releasable restraining members extending over and radially constraining lengthwise portions of said endograft.
9. The delivery system of claim 8 wherein said restraining members are releasably attached to said nosecone.
10. The delivery system of claim 8 wherein said restraining members are configured to be released by severing said restraining members.
11. The delivery system of claim 8 wherein said restraining members are absorbable and are configured to be released by absorption.
12. The delivery system of claim 8 wherein said restraining members are individually releasable.
13. The delivery system of claim 12 wherein said restraining members are sequentially releasable.