Patent Application
20100139984
The present invention relates to a rotary drive for applying rotary torque to a shaft that has axial vibration applied such as, but not restricted to vibrational drilling.
Vibrational drilling involves vibrations being passed down into a drill string to a bit or its equivalent whilst the drill string and the bit is rotated about its rotational axis. Preferably such vibrations are primarily axial.
Various forms of vibrational apparatus have been proposed as vibrational heads adapted to impart such axial vibrations down a drill string. These range from rotated eccentrics to shuttle including arrangements (fluid powered shuttles under rotary valve control, mechanically rotated shuttles that shuttle as a consequence of magnetic interactions and/or shuttle including vibrational heads where vibrational output into a drill string does not require connection to the shuttle) as disclosed in our (PCT/NZ2004/000128) WO2004/113668 published 29 Dec. 2004, PCT/NZ2005/000047 (WO2005/087393 published 23 Sep. 2005), PCT/NZ/2005/000329 and PCT/NZ2006/000244.
The full content of the aforementioned specifications is hereby here included by way of reference but subject to the following rider:
The present invention has as an object the desirability of providing a rotational input into the spindle of, or for, a drill string but at least to some extent to isolate the mechanism providing such an input from at least the axial vibrations to be passed via the spindle into the drill string. Such an arrangement is to reduce destructive wear and/or vibrational damage.
It is a further or alternative object of the present invention to provide a gear drive suitable for imparting a rotary motion into a drill string, or the spindle for a drill string, yet which is isolated from at least some of the at least axial vibration to be imparted into the drill string via the spindle from a vibrational head.
It is a further and alternative object of the present invention to provide a motored (eg; hydraulic motored) gear drive into a driven gear carried by a carriage that is axially movable within limits on guides disposed about the spindle of, or for, a drill string, such action of the carriage on the guides (as an array about the spindle fixed in relation thereto) being able to impart rotary motion from the driven gear into the spindle and thence, in use, the drill string.
It is a further an alternative object of the present invention to provide an assembly adapted for suspension from a vibrational apparatus (eg; vibrational head) itself suspended preferably so as to support the weight not only of the drill string but at least part of the drive train to rotate the drill string.
It is still a further alternative of the present invention to provide a vibrational drilling assembly where the weight of the drill string and its bit, at least some of the drive train to impart rotational drive to the drill string and the vibrational head is supported from a structure with respect to which there can be movement as a result of movement upwards against at least one gas bag and downwards against at least one gas bag.
In one aspect the invention is a rotary drive assembly of or for a drill string or other shaft, the assembly comprising or including
Preferably the adaptation to connect to vibrational apparatus is for a shuttle including vibrational head to which such an adaptation is to be connected or is connected, the output vibrationally not being directly from the shuttle, but from some structure relative to which the shuttle shuttles.
Preferably the shuttle axis is rectilinear and is aligned with the axial direction, i.e.; the rotational axis of the spindle and/or the rotational axis of the drill string or other shaft.
Preferably said spindle is to be aligned axially with the drill string or other shaft.
Preferably the vibrational head is a vibrational head of any of the kinds described in our abovementioned patent specifications.
Preferably said shuttle is driven to shuttle as a result of both (i) an input of a rotational drive on the shuttle and (ii) magnetic interactions capable of causing a shuttling.
Preferably such a shuttle imparts vibration to the structure from which vibration is carried to said adaptation via a fluid (most preferably a liquid).
Preferably the liquid in the vibrational apparatus can be subject to some bleeding from a chamber or chambers under impact but nevertheless leads to the avoidance of solid to solid contact at the limits of shuttling. Such bleeding also serves the purpose of allowing remote cooling of such liquid oil.
Preferably the adaptation is a structure relative to which the spindle and its pins can rotate, such rotation being about the spindle axis which preferably is aligned with the axial pathway for vibrational feed into the spindle from said adaptation.
Preferably the driven gear is mounted on a sleeve encompassing structure, said sleeve encompassing structure carrying the mounted gear such gearing mounting (preferably with preloaded axially loaded bearing assemblies) being adapted to rotate coaxially about the spindle axis as part of a carriage that includes said sleeves.
Preferably the vibrational apparatus, or adaptation to connect to the vibrational apparatus (e.g. non rotational axially movable member), is thrust bearing mounted relative to the spindle.
In another aspect the invention consists in a rotary drive assembly of or for a drill string or other shaft, the assembly comprising or including
Preferably the carriage is movable, on the slides thereby providing relative axial movement of said carriage and the geared drive relative to said slides and thus both (i) the vibrational apparatus or adaptation and (ii) the spindle.
In yet a further aspect the present invention consists in a drilling assembly comprising or including
Preferably such an arrangement includes a rotary drive assembly of any aspect in accordance with the present invention.
In a further aspect the present invention consists in the use of a sliding mount or sliding mounts (“mount(s)”) for a gearbox or gear train carriage, the gearbox or gear train being about a spindle axis able to rotate the spindle under tangential forces applied to the mount(s), the spindle being for connection into a vibrational drill string.
In a further aspect the present invention consists in a gear box or gear train having a drive substantially as herein described, particularly with respect to at least partial isolation from vibration, of apparatus substantially as herein described with reference to any one or more of the accompanying drawings.
In another aspect the invention is a drive assembly suitable for a spindle connection to a drill string or other shaft, the assembly comprising or including
In still another aspect the invention is spindled apparatus for supporting, vibrating and driving a drill string or other shaft, the apparatus comprising or including
a carriage assembly on part of the spindle slidable on an axis coincident with and/or parallel to the spindle's rotational axis, and
In yet another aspect the invention is spindled apparatus for supporting, vibrating and driving a drill string or other shaft, the apparatus comprising or including
In yet a further aspect the present invention consists in apparatus substantially as hereinafter described with reference to any one or more of the accompanying drawings.
The present invention also relates to an axial drive for vibrational drilling.
Reference herein to “other shaft” however need not be that of a drilling system e.g. could be for part of a materials reduction system.
In our aforementioned patent specifications there is disclosure of a vibrational head used in conjunction with a transmission down into a drill string.
It is desirable, from time to time, to ensure that the overall girth or bulk of the vibrational head when viewed transversely of the spindle axis (that axis that is to be connected into the top of the drill string) is sufficiently small to be manoeuvred down through gaps and/or into holes.
In our aforementioned patent specifications, we disclose a type of vibrational head dependent upon a mechanical input to a rotatable shuttle able to shuttle, as a result of magnetic interactions, in a direction along or parallel to its rotational axis, that axis also being preferably aligned with the spindle axis, thereby to provide vibration in its surrounds that transmits to the drill string.
The present invention envisages and has as an alternative or object a non belt drive or an arrangement (optionally including a gear box) where there is no need for any tangential driving of the rotation of the shuttle which would have the affect of increasing girth or bulk. An object is an axial rotational drive i.e. in line.
It is a further or alternative object to provide assemblies whereby both vibration and torque can be transmitted into a shaft or drill string.
In another aspect the invention is, or associated with other aspects of the invention there is, vibrational apparatus connectable to, connected to or suitable for connection (directly or indirectly) to a drill string, the apparatus comprising or including
Please note that the interaction between the shuttle and the drive shaft is preferably a spline or dogged slide interrelationship.
Preferably said structure to provide the vibrational output from at least part of the vibrational apparatus is at least a partial housing or extension from a housing of the shuttle. The output can ultimately be that of a spindle not moving axially with the shuttle.
Preferably the structure to provide a vibrational output is associated or associable with apparatus as previously defined (ie; a rotary drive assembly, a drilling assembly, sliding mounts for a gear box carriage, etc. as previously). It is the vibrational output as an input to that apparatus that is isolated from the carriaged sleeves or the like (associated with the gear drive) that acts through the guides or slides of the spindle.
In a further aspect the present invention consists in (I) an axial drive of the rotation of a shuttle in apparatus of any aspect of the present invention, the axial drive allowing relative axial movement between an input member and the shuttle and/or (II) a hydraulic motored geared drive of a axially moveable carriage on a spindle assembly to rotate the spindle as it axially vibrates independently of the carriage.
As used herein the term “and/or” means “and” or “or”, or both.
As used herein the term “(s)” following a noun includes, as might be appropriate, the singular or plural forms of that noun.
This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more of said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.
A preferred form of the present invention will now be described with reference to the accompany drawings in which
A preferred form of the present invention is as shown in
In
It is sufficient if there is vertical support from any appropriate crane, structure, frame or other support member for either both 4 and 5 or member 3. There is an ability for the overall structure as shown in
It can be seen therefore that the gas or air bags have the ability to balance increasing load on the drill string or increasing load of the drill string without damping of the vibrational input wanted in the drill string via the spindle 6 from the contained shuttling. All of this is irrespective of drive force or weight as it is always suspended and can always “wobble” upwardly or downwardly.
Such an arrangement of support is quite different from prior art vibrational damping.
Shown in
Shown as part of 8 are an array of fixed magnets 9 and an array of fixed magnets 10, each to be interacted with by corresponding or other arrays 11 and 12 respectively of the shuttle as the shuttle rotates thereby with the alternating polarities causing the shuttling.
The shuttle rotates under the action of a splined axial drive from the input shaft 7 which interacts via dogs, splines or other means shown generally as 13 thereby allowing the shuttle to move upwardly and downwardly as a result of the magnetic interactions as they occur during rotation of the shuttle 8 under the input rotational action from 7 via 13.
The movement of the shuttle is up and down with little in the way of fetter on such movement as a consequence of the drive it receives axially from the input shaft 7.
Whilst there may be the prospect of an axial drive exteriorly of the shuttle with a similar ability to have relativity of movement axially, the preferment is the internal receipt of the member 7 by the shuttle assembly 8.
The operation of the shuttle has been described previously in the aforementioned patent specifications.
Optionally provision can be made to ensure solid to solid contact avoidance by use of vibrational passage into a liquid. Nevertheless there can be metal choices and/or synthetic material choices, or sequences thereof, or assemblies thereof, that do not result in damage from contact despite impacts and relativity of rotation.
Carried by the shuttle, but not as a linked mechanical out put, is a member 14 which dips its partitioning member 16 into a member 16 partitioned chamber 15 having some liquid or other fluid content. Preferably the content is a liquid (such as oil). Preferably that oil is pressurisable independently of the pressures created by the shuttling thereby to enable tuning of the nature of the vibrational transfers. That oil is preferably able to move to some extent from one partition to the other of chamber 14. The oil irrespective acts as a vibration transmitting cushion of the axial downward limit and the axial upward limit of the shuttle 8. This avoids solid to solid contact, eg; of the magnet banks 9 and 11 and/or 10 and 12. The act of pressurising the oil allows a flow circuit for cooling purposes. Pressurisation can also allow sacrificial oil flow through seals for lubrication purposes.
Such an arrangement is a variation of that previously disclosed but nonetheless provides vibrational output dependent on shuttling but not taken directly by a rigid mechanical link from the shuttle, ie; the shuttling through the interaction of the members 14 and 16 on the liquid as a cushioning provides a vibrational output of the overall structure of the shuttle and its housing into component 17 (variously referred to previously as an “adaptation” to receive the vibration from the vibrational head or the “vibrational head” or part thereof).
The arrangement from member 17 downwards as well as its connections upwardly thereof is what is depicted in greater clarity in
It can be seen however there is a drive down into the spindle of the axial vibration carried through the structure.
The spindle 6 itself is rotatable under the action of one or more motors (preferably hydraulic motors 18) which act to rotate input gears 19 which in turn drive a carriage carried gear 20, the carriage (generally shown as 21) is an assembly around sleeves or having bores, chambers or yokes.
It can be seen that the guides or pins 22 allow the carriage 21 to move upwardly and downwardly within limits thereby driving the associated spindle 6 under the action of applying tangential force via the pins or guides 22 to the spindle. The arrangement however has the desirable outcome of ensuring the motor, its housing carried by the carriage 21 etc. is or can be largely isolated from the vibrational downput to the spindle 6 yet it nevertheless provides a capability of providing a high torque rotational drive.
That rotational pathway, as well as the role of the thrust bearings 23 and the other bearing structures 24 will now be described in greater detail.
In the preferred form of the present invention the paths of rotary power transfer, the paths of rotary power transfer and vibrational transfer can be described as follows. Also reference will be made to the axial float described in our patent specification numbers aforesaid.
The input torque from the hydraulic motors is transferred through the pinion gears (B) to the main gear (C) which is fastened to the two centre carrier halves (D). These carriers retain the bushes (E) (ie; the sleeves) that are oil fed internally to reduce the friction between themselves and the chrome plated drive pins (F).
Please note all of the above parts except for the drive pins are not subject to direct vibration.
The carrier halves (D) are supported in the gearbox housing (not shown) by the two deep groove ball bearings (G). Because these bearings are subject to a small amount of residual axial vibration, we need to pre load the outer bearing ring in an axial direction. This is achieved by the multiple compression springs (H) reacting between the outer bearing race (G) and the gearbox housing (not shown).
Part A centre shaft cannot rotate, but does move axially at the amplitude and frequency supplied via the oil bath from the vibrational head as a consequence of shuttling. This vibration is then transferred through the two spherical roller thrust bearings (I) and then into part (J)+(K)+(L) and finally out through the output spindle (M).
Because of the thrust supplied via the gas (air) bellows at the back or top end of the machine, we have a +/− limit (e.g. of 35 mm) built into the spindle design. This movement takes place between the bushes (E) and the drive pins (F).
Another way of describing this is that the gearbox housing and parts B, C, D, E, G and H are all stationary and the rest of the assembly slides inside it.
| Number | Date | Country | Kind |
|---|---|---|---|
| 554256 | Mar 2007 | NZ | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/NZ2008/000053 | 3/13/2008 | WO | 00 | 9/29/2009 |
