This invention relates in general to earth formation drilling tools and methods, and more particularly to an underreaming and stabilizing tool to be put into service in a drilling hole and a method for its use.
Earth formation drilling is often accomplished using a long string of drilling pipes and tools coupled together. The drilling string is rotated together in order to rotate a cutting bit at the end of the string. This cutting bit creates the hole which the rest of the drilling string moves through. For various reasons, it may be desirable to widen the walls of the hole after it has been created by the cutting bit. Bore-hole underreamers exist to accomplish the widening of the hole. An underreamer may be coupled to the drilling string between two other elements of the drilling string. It may then be sent down hole with the drilling string, rotating with the drilling string, and widening the hole.
Various underreamer designs exist. Some have fixed cutting blades around the periphery of the underreamer and some have expandable blades or arms. Various types and hardness of earth formations also exist. Aggressive blades, extending quickly and/or relatively far beyond the periphery of the underreamer body, may be used in soft formations; and less aggressive blades, extending more slowly and/or a shorter distance beyond the periphery of the underreamer body, may be used in harder formations. Different types of formations may exist down the length of a drilling hole, and it may be desirable to widen the hole through each of these formation types. If the blades or arms with which the underreamer is equipped are not suitable for the types of formations being widened, the underreamer may need to be replaced. This generally involves pulling the drill string up from the hole, disconnecting the underreamer, and connecting an underreamer equipped with blades or arms that are suitable for the formation type. This may require a drilling operator to have several underreamers on hand as well as the tools required to change underreamers. The increased inventory requires a greater capital investment, more storage space, and greater maintenance costs than having a single underreamer.
Over the lifetime of the underreamer the blades or arms of the underreamer may become worn. When the underreamer is no longer able to perform a widening of the drilling hole, it may be withdrawn from the drilling hole and disconnected from the drilling string. A new underreamer may be put in its place, and the worn underreamer may be sent for retooling and refurbishment. Sending the worn underreamer away for retooling and refurbishment may result in costly down time or increased inventory and maintenance costs by requiring a replacement underreamer to be kept available.
In accordance with the present invention, the disadvantages and problems associated with underreamer cutter wear and replacement have been substantially reduced or eliminated. In particular, an underreamer is provided in which the cutter arms may be easily replaced, thereby reducing the number of different underreamers which need to be kept on hand, and reducing costly downtime.
Particular embodiments of the present invention may provide a drilling tool that includes a tubular body defining a longitudinal axial cavity extending therethrough. The tubular body also defines at least one radial guidance channel extending radially from the axial cavity through the tubular body. A cutter element is disposed in the at least one radial guidance channel and includes an internal surface inclined at an angle to a longitudinal axis of the tubular body. The drilling tool also includes a wedge element having an external surface configured to engage the internal surface of the cutter element and to direct the cutter element from a retracted position to an extended position as the wedge element moves from a first position to a second position.
Certain embodiments of the present invention may also include a drive pipe disposed within the axial cavity and coupled to the wedge element. The drive pipe may be configured to move the wedge element from the first position to the second position as the drive pipe moves from a first longitudinal position to a second longitudinal position. Certain embodiments may also include the drive pipe defining a longitudinal slot along an intermediate portion of the drive pipe. The drive pipe may also define a peripheral slot disposed adjacent a first end of the longitudinal slot. The drive pipe may be configured to permit the wedge element to slide within the longitudinal slot when the drive pipe is in a first angular position and to fixedly couple the wedge element to the peripheral slot of the drive pipe as the drive pipe is rotated from the first angular position to a second angular position. In another particular embodiment the drive pipe may define at least a first longitudinal groove having a length corresponding to a distance between the first and second longitudinal positions of the drive pipe. The tubular body may further define at least a first aperture aligning with the first longitudinal groove when the drive pipe is in the second angular position. A generally cylindrical immobilizing element may pass through the first aperture and protrude into the first longitudinal groove.
A method according to the one embodiment of the present invention may include installing a cutter element and a wedge element at least partially within a radial guidance channel of a tubular body by passing the cutter element through a longitudinal axial cavity of the tubular body. The cutter element and the wedge element may then be moved radially outward from the longitudinal axial cavity at least partially into the radial guidance channel. The cutter element may be moved from a retracted position to an extended position by moving the wedge element from a first longitudinal position to a second longitudinal position.
Certain embodiments may include coupling the wedge element to the cutter element before installing the cutter element and the wedge element at least partially within the radial guidance channel. Another particular embodiment may include installing the drive pipe in the axial cavity by: orienting the drive pipe in a first angular position, inserting an end of the drive pipe into an end of the tubular body, sliding the drive pipe into the axial cavity, and rotating the drive pipe to a second angular position.
A particular alternative embodiment of the present invention may include increasing a fluid pressure of a drilling fluid circulating inside an axial cavity of a tubular body. A surface pressure on a piston of a drive pipe disposed within the axial cavity of the tubular body is increased by increasing the fluid pressure of the drilling fluid. A longitudinal movement of the drive pipe and a wedge element coupled to the drive pipe is achieved by increasing the surface pressure on the piston. And a radial movement of a cutter element disposed in a radial guidance channel of the tubular body is achieved by directing the longitudinal movement of the drive pipe and the wedge element.
Technical advantages of certain embodiments of the present invention include an underreamer with cutter elements which are easily replaced, yet held securely within the underreamer. The cutter elements are installed from the inside of the body of the underreamer into radial guidance channels which prevent the cutter elements from extending past a designed extension point. In this manner, the cutter elements of the underreamer may be easily changed to less worn cutter elements or to cutter elements which are more appropriate for a particular formation type. This feature may reduce or eliminate the need to keep multiple underreamers available.
Additional technical advantages of the present invention include radially movable cutter elements which move in response to fluid pressure changes. The fluid pressure acting on the cutter elements may be increased to extend the cutter elements and decreased to cause a retraction of the cutter elements.
Further technical advantages of the present invention include activation and deactivation devices. The activation device keeps the cutter elements in a retracted position until underreaming is desired, and the deactivation device keeps the cutter elements in the retracted position after underreaming is complete. In this manner, the underreamer is not activated when underreaming is not desired. This also avoids unnecessary wear on the underreamer.
Other technical advantages of the present invention will be readily apparent to one skilled in the art from the following figures, descriptions, and claims. Moreover, while specific advantages have been enumerated above, various embodiments may include all, some, or none of the enumerated advantages.
For a more complete understanding of the present invention and its advantages, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:
The present invention relates to an underreaming and stabilizing tool to be used in a drilling hole. The tool includes a tubular body suitable for coupling with a drilling string and/or other drilling tools. The tubular body may have an axial cavity which is open towards the outside through at least one radial guidance channel. A cutter element may be arranged so as to be movable radially in each radial guidance channel. The tool also includes wedges that, through a longitudinal movement inside the tubular body, lead to radial motion of each cutter element in its radial guidance channel.
It has become increasingly necessary, during drilling in hard and abrasive geological formations, to have underreaming tools provided with many cutter elements having the form of large arms. The underreaming arms are increasingly elongated and equipped with a high number of cutting tips. The underreaming arms underream the drilling hole during a descent of the tool downwards and may be provided with reinforced diamond dome parts for stabilizing the tool during underreaming and parts for underreaming the hole while raising the underreaming tool towards the surface.
The tools currently available have the drawback of being suitable only for use in one type of geological formation. Upon a change of geological formation, the underreaming tool must be completely replaced. The whole tool must be extracted from the drilling sting and replaced with another tool whose configuration is better suited for underreaming the drilling hole in the new geological formation. The same applies in the case of wear or failure of the cutter elements. This results in a significant operating cost.
The teachings of the present invention provide an underreaming and stabilizing tool that provides increased flexibility according to the geological formations in which it is used, and ease of replacement of the cutter elements due to wear.
The previously enumerated problems have been solved by an underreaming and stabilizing tool which includes a drive pipe mounted inside the axial cavity so as to move longitudinally therein. The drive pipe has a longitudinal axis about which it is capable of pivoting. The tool also includes at least one wedge element per cutter element. Each wedge element is supported in a detachable manner at the periphery of the drive pipe. Each wedge element and the drive pipe are, in a first angular position of the drive pipe, capable of moving independently longitudinally. In a second angular position of the drive pipe, each wedge element is held by the drive pipe such that each wedge element moves longitudinally with the drive pipe. The tool also includes detachable stopping mechanisms which are capable of immobilizing the drive pipe in its second angular position, while allowing its longitudinal movements.
This tool, therefore, allows easy replacement of the wedge elements by allowing detachment from the drive pipe on which the wedge elements are supported. Therefore it is possible without difficulty to replace the wedge elements with other wedge elements having a different configuration. Faced with a hard geological formation, cutter elements can be provided that react with more flexibility during underreaming because they rest on wedge elements with a steep slope. Faced with a crumbly geological formation, there can be provided, in the same tool, cutter elements that retract more slowly, since the wedge elements will then be provided with a gentler slope. Such a conversion of the tool therefore requires only replacement of the wedge elements and substitution of the cutter elements with other cutter elements adapted to the replaced wedge elements. Thus, there can also be provided, in the same radial guidance channels, cutter elements having different active lengths without having to change tools.
Moreover, upon wear of the cutter elements, the cutter elements can be replaced quickly, as will be described in a more detailed manner below.
According to one embodiment of the invention, a stopping mechanism may be provided that may comprise at least one aperture in the tubular body and at least one groove extending longitudinally on the periphery of the drive pipe over a length corresponding to the desired longitudinal sliding of the drive pipe. When the drive pipe is in the second angular position, the groove faces the at least one aperture. The stopping mechanism may also include an immobilizing element passed through the at least one aperture in order to enter the at least one groove to immobilize the drive pipe in its second angular position without preventing its longitudinal movements. In order to allow, on a single tool, easy adjustment of the permitted longitudinal travel for the drive pipe, provision has been made, according to the invention, that the stopping mechanism comprises a number of apertures and a corresponding number of grooves which have mutually different lengths. According to the required sliding length of the drive pipe, the immobilizing element is passed through the aperture situated facing the appropriate groove. The tool also comprises a way of closing off the unused apertures. For example, if the required slope of the wedge elements must be steeper or if the radial movement of the cutter elements protruding out of the body of the tool must be small, it is sufficient to limit the longitudinal movement of the drive pipe by introducing the immobilizing element into a groove having a relatively shorter length.
According to one embodiment of the invention, the inclined internal surface of each cutter element and the inclined external surface of each wedge element on which the cutter element rests are provided with mutual holding mechanisms in the radial direction. The holding mechanisms are arranged so that the cutter element in the high position in its radial guidance channel performs a radial descent to a low position by retraction on the part of the holding mechanisms of said at least one wedge element during the longitudinal movement thereof. The pressure of the cutter elements radially outwards and the retraction thereof inside the tubular body therefore result solely from cooperation between wedge elements and a corresponding cutter element, confined in a channel which is used solely for radial guidance. The result of this is that, irrespective of the slope of the cooperating surfaces of the wedge elements and the cutter element, the length of the latter or the required extension thereof out of the body of the tool, the tubular body and the drive pipe remain the same.
According to one embodiment of the invention, the drive pipe comprises a piston which separates, in the tubular body, a first section in which a hydraulic fluid is under an internal pressure and a second section, which is in communication with the outside through said at least one radial guidance channel where the at least one wedge element and corresponding cutter element are housed. By a simple difference in pressure applied between two sections of the tubular body, it is possible to drive the wedge elements longitudinally and put the cutter elements into service for underreaming the hole and/or stabilizing the tool in this hole.
The present invention also concerns a method for using an underreaming and stabilizing tool to be put into service in a drilling hole. The method may include axial introduction of each cutter element equipped with at least one wedge element into the axial cavity of the tubular body facing a corresponding radial guidance channel. Each cutter element, equipped with its at least one wedge element, may be positioned and held in its radial guidance channel. The method may then include introduction of the drive pipe into the axial cavity of the tubular body, in a first angular position, and relative sliding between this drive pipe and said at least one radially fitted wedge element, as far as an appropriate position. The method may then include pivoting the drive pipe to a second angular position in which it is capable of driving said at least one wedge element in its longitudinal movements. The drive pipe may be immobilized in this second angular position, while still allowing its longitudinal movements.
Such a method allows a particularly easy and quick mounting and dismantling of the tool by axial introduction of all the other elements into the cavity of the tubular body. A simple rotation of the drive pipe immobilizes the wedge elements on the drive pipe in the longitudinal direction. Next, a simple immobilization of the drive pipe in its new angular position immediately allows the tool to be put into service.
Furthermore, introduction of the cutter elements axially, or through the inside of the tubular body, reduces or eliminates the risk of them becoming detached from the tool during operation. This is because the cutter elements are immobilized in their radial guidance channel, for example, by appropriate limit stops that prevent the portions of the cutter elements interacting with the limit stops from extending radially past the limit stops.
According to a further embodiment, the method also comprises, before the step of axial introduction of each cutter element, arranging on at least one inclined internal surface of each cutter element at least one wedge element having an external surface inclined in the same way. During axial introduction, the cutter element and the wedge element remain fixed to one another by, for example, a shear pin. The wedge element and the cutter element may be separated during drilling by a threshold hydraulic pressure of a drilling fluid acting on a piston of the drive pipe sufficient to shear the shear pin.
Other details and particular features of the invention will emerge from the description given below on a non-limiting basis and with reference to the accompanying drawings.
As illustrated in
In each radial guidance channel 3 and 4, a cutter element 5 and 6, respectively, is arranged so as to be movable radially, with respect to a longitudinal central axis 8 of the tubular body 1. Each cutter element comprises, in the example illustrated, an external surface equipped with cutting tips which has a front part 7 inclined towards the front with respect to longitudinal axis 8, a central part 9 substantially parallel to the axis 8, and a rear part 10 inclined towards the rear with respect to axis 8. Front part 7 is intended to produce an underreaming of the drilling hole during its descent. Central part 9 is intended to stabilize the tool with respect to the underreamed hole. Rear part 10 is intended to produce an underreaming of the drilling hole during raising of the drilling string.
For the purposes of this description, longitudinal movement is defined as movement at least substantially parallel to the longitudinal axis 8. Radial movement is defined as movement at least substantially perpendicular to, or in a plane at least substantially perpendicular to, longitudinal axis 8.
The tool according to the invention also comprises a drive pipe 11 mounted inside axial cavity 2 so as to be able to perform longitudinal movements therein according to a hydraulic pressure. Drive pipe 11 is also capable of pivoting or rotating about the aforementioned longitudinal axis 8.
As illustrated in
The tool according to the invention also comprises, in the example illustrated, two wedge elements 17 and 18 per cutter element 5 and 6. These wedge elements are supported by drive pipe 11. In alternative embodiments, there could be provided a single wedge element per cutter element or more than two wedge elements per cutter element, according to operational requirements.
Each cutter element 5 and 6 may have at least one inclined internal surface disposed at an angle to longitudinal axis 8. In the example implementation illustrated, cutter element 5 has two inclined internal surfaces 19 and 20. Each wedge element 17 and 18 may have an inclined external surface 21 corresponding to inclined internal surfaces 19 and 20 that rests on the internal surface 19 or 20 of the corresponding cutter element.
As illustrated in
Furthermore, for mounting, each wedge element is fixed on its respective cutter element by a shear pin 22 (see
Referring to
Drive pipe 11 also has at its periphery peripheral slots 24 and 25 into each of which a wedge element 17 or 18 can move when the drive pipe is caused to pivot about its axis 8 between a first angular position illustrated in
In this second angular position, wedge elements 17 and 18 are held radially inside peripheral slots 24 and 25, respectively, as a result of the peripheral slots having a dovetail-shaped cross-section and the edges of wedge elements 17 and 18 widening out in a corresponding manner at 26 and 27 (see
The tool may also comprise detachable stopping mechanisms which are capable of immobilizing drive pipe 11 in its second angular position while allowing its longitudinal movements. These stopping mechanisms may comprise at least one aperture in tubular body 1 and at least one groove which extends longitudinally on the periphery of drive pipe 11. In the example illustrated, drive pipe 11 is provided with three apertures and three grooves. Two apertures 28 and 29 are depicted in particular in
The aforementioned stopping mechanisms also comprise an immobilizing element 32 that passes through aperture 28 situated facing groove 30. Immobilizing element 32 passes into groove 30 and thereby prevents drive pipe 11 from performing a pivoting motion while not hindering its longitudinal sliding within the limits imposed by the length of groove 30. A drive pipe 11 including grooves of differing lengths allows selection of the length of longitudinal displacement of drive pipe 11. The longitudinal displacement of drive pipe 11 may be adjusted to achieve the desired radial displacement of cutter element 5 given the slope of wedge elements 17 and 18. The longitudinal displacement is selected by installing the immobilizing element 32 into the aperture corresponding to the groove having a length substantially equal to the desired length of longitudinal displacement. Once the immobilizing element 32 has been installed, the other apertures may be equipped with plugs 33.
During its longitudinal sliding, drive pipe 11 is brought from the position depicted in
Advantageously, piston 13 has a passage in the form of at least one duct 36 of small diameter (see
As illustrated in
Cutter elements 5 and 6, equipped with their two wedge elements, are then introduced axially inside axial cavity 2 of tubular body 1 in the direction of arrow F1 of
The next step is illustrated in
When wedge elements 17 and 18 arrive facing peripheral slots 24 and 25, drive pipe 11 is pivoted about axis 8 according to the double arrow F4 of
Drive pipe 11 can be immobilized in its second angular position by immobilizing element 32. Immobilizing element 32 is passed through an appropriate aperture, for example aperture 28, and a groove, for example groove 30, whose length corresponds to the sliding length chosen for the application of the tool.
As noted, the mounting and the dismantling of the tool is relatively simple and quick. Cutter elements 5 and 6 can easily be replaced with new cutter elements, and other models of cutter elements can be introduced into the tool without having to replace the entire tool.
The tool according to the invention also comprises an activation device which is capable of keeping drive pipe 11 in its initial position depicted in
As can be seen in particular in
According to another example implementation illustrated in
An activation ball 48 can be sent from the surface, coming to lodge against a terminal narrowing 49 of extension pipe 41. The application of activation ball 48 as depicted in
The tool according to the invention can also advantageously be provided with a drive pipe capture device. In the example implementation illustrated in
A first elastic catch ring 55 is housed in an internal slot 58 in sleeve 52 and can therefore slide with sleeve 52 over lengthening piece 51. A second elastic catch ring 59 is housed in an internal slot 60 formed between sockets 53 and 54 so as to be able to slide over sleeve 52.
In the initial position of drive pipe 11, and when the tool is being put into service, sleeve 52 is kept longitudinally inside fixed socket 53 by a shear pin 61. The drilling mud passes inside sleeve 52, lengthening piece 51, and drive pipe 11.
When the operation of the tool has to be stopped, for example in order to be raised to the surface, a second ball 62 with a diameter greater than that of sleeve 52 is sent into the drilling string. Ball 62 is stopped at the input of sleeve 52, closing off the passage. Through the mechanical impact of ball 62 and the great increase in fluid pressure, shear pin 61 is sheared off and the sleeve 52 can slide downwards.
During this downward sliding, a peripheral slot 64 in sleeve 52 takes up a position facing second elastic catch ring 59. Second elastic catch ring 59 lodges in peripheral slot 64, thus fixing together sleeve 52 and fixed sockets 53 and 54. Sleeve 52 is thereby also fixed to joining element 57 of tubular body 1. When the pressure is reduced, first elastic catch ring 55 lodges in a peripheral slot 63 provided in lengthening piece 51 of drive pipe 11. This occurs because drive pipe 11 is raised into its initial position by return spring 42, which fixes lengthening piece 51 and drive pipe 11 with the sleeve 52. In this position, drive pipe 11 is captured by tubular body 1 and cannot move anymore. As the upstream end of sleeve 52 is provided with lateral holes 66, the drilling mud can, in this capture position, continue to circulate by passing laterally around ball 62 in a space 67 formed between socket 53 and sleeve 52, through lateral holes 66, and through sleeve 52.
In an alternative embodiment, a latch element may longitudinally keep drive pipe 11 in its initial position in tubular body 1. An electrical control similar to those already known in the art may be used to actuate the latch element. The electrical control may be situated on the surface or integral to the drilling string and may be electrically coupled to the latch. The electrical control may be operable to actuate the latch between open and closed positions and thereby release and capture drive pipe 11.
Distinct from the above described embodiments, the wedge elements 117 and 118 may be rigidly connected to each other. In the illustrated embodiment, wedge elements 117 and 118 are coupled together by a rectangular cross member 150 and have a common base 151. Wedge elements 117 and 118 may be formed as a single piece with cross member 150 and base 151 by casting or billeting the entire assembly, or the pieces may be coupled together after being formed by welding or other appropriate fixing method. Further, the shape of cross member 150 is not limited to a rectangular shape and may be practically any shape. Likewise, the number of wedge elements is not limited to two, but may be practically any desired number.
As drive pipe 111 is installed into tubular body 101, base 151 of wedge elements 117 and 118 may slide along a longitudinal slot as described above. Drive pipe 111 may then be rotated into its second angular position, or installed position, and base 151 may slide into peripheral slot 124. Base 151 and peripheral slot 124 may form a dove-tail joint as described above. This arrangement allows for installation of the assembled wedge elements 117 and 118 with cutter elements 105 prior to installation of drive pipe 111, while providing a secure coupling of wedge elements 117 and 118 to drive pipe 111 when drive pipe 111 is in its second angular position.
Also similar to the embodiments described above, wedge elements 117 and 118 may be coupled with cutter element 105 by dove-tail slot 139 and molding 138. This assembly may be held together in an initial, unactivated position by shear pin 122. An advantage of rigidly coupling wedge elements 117 and 118 is that only one shear pin 122 is needed to couple wedge elements 117 and 118 to cutter assembly 105. Shear pin 122 is designed to be destroyed during activation and using only one shear pin 122 reduces waste and assembly time.
The embodiment illustrated in
Numerous other changes, substitutions, variations, alterations and modifications may be ascertained by those skilled in the art and it is intended that the present invention encompass all such changes, substitutions, variations, alterations and modifications as falling within the spirit and scope of the appended claims. Moreover, the present invention is not intended to be limited in any way by any statement in the specification that is not otherwise reflected in the claims.
This application is a Continuation-in-Part of International Patent Application Ser. No. PCT/BE2004/000057 entitled “Underreaming and Stabilizing Tool and Method for Its Use” filed on Apr. 21, 2004.
Number | Name | Date | Kind |
---|---|---|---|
336187 | Wells | Feb 1886 | A |
1411484 | Fullilove | Apr 1922 | A |
1454843 | Brown | Jun 1923 | A |
1485642 | Stone | Mar 1924 | A |
1607662 | Boynton | Nov 1926 | A |
1631449 | Alford | Jun 1927 | A |
1671474 | Jones | May 1928 | A |
1686403 | Boynton | Oct 1928 | A |
1750629 | Crum | Mar 1930 | A |
1772710 | Denney | Aug 1930 | A |
1804850 | Triplett | May 1931 | A |
1878260 | Bunker | Sep 1932 | A |
1881035 | Triplett | Oct 1932 | A |
1921135 | Santiago | Aug 1933 | A |
2060352 | Stokes | Nov 1936 | A |
2169502 | Santiago | Aug 1939 | A |
2239996 | Chappell | Apr 1941 | A |
2271472 | Balduf | Jan 1942 | A |
2427052 | Grant | Sep 1947 | A |
2438673 | McMahan | Mar 1948 | A |
2450223 | Barbour | Sep 1948 | A |
2499916 | Harris | Mar 1950 | A |
2710172 | Kammerer, Jr. | Jun 1955 | A |
2754089 | Kammerer, Jr. | Jul 1956 | A |
2758819 | Kammerer, Jr. | Aug 1956 | A |
2809015 | Phipps | Oct 1957 | A |
2822150 | Muse et al. | Feb 1958 | A |
2834578 | Carr | May 1958 | A |
2872160 | Barg | Feb 1959 | A |
2882019 | Carr et al. | Apr 1959 | A |
3105562 | Stone et al. | Oct 1963 | A |
3123162 | Rowley | Mar 1964 | A |
3180436 | Kellner et al. | Apr 1965 | A |
3224507 | Cordary et al. | Dec 1965 | A |
3351144 | Park | Nov 1967 | A |
3365010 | Howell et al. | Jan 1968 | A |
3425500 | Fuchs | Feb 1969 | A |
3433313 | Brown | Mar 1969 | A |
3556233 | Gilreath et al. | Jan 1971 | A |
3749184 | Andeen | Jul 1973 | A |
3974886 | Blake, Jr. | Aug 1976 | A |
4055226 | Weber | Oct 1977 | A |
4081042 | Johnson et al. | Mar 1978 | A |
4091883 | Weber | May 1978 | A |
4141421 | Gardner | Feb 1979 | A |
4177866 | Mitchell | Dec 1979 | A |
4186810 | Allan | Feb 1980 | A |
4190124 | Terry | Feb 1980 | A |
4411557 | Booth | Oct 1983 | A |
4458761 | Van Vreeswyk | Jul 1984 | A |
4503919 | Suied | Mar 1985 | A |
4589504 | Simpson | May 1986 | A |
4660657 | Furse et al. | Apr 1987 | A |
4821817 | Cendre et al. | Apr 1989 | A |
4842083 | Raney | Jun 1989 | A |
4889197 | Bøe | Dec 1989 | A |
4915181 | Labrosse | Apr 1990 | A |
5010967 | Desai | Apr 1991 | A |
5036921 | Pittard et al. | Aug 1991 | A |
5060738 | Pittard et al. | Oct 1991 | A |
5086852 | Van Buskirk | Feb 1992 | A |
5139098 | Blake | Aug 1992 | A |
5184687 | Abdrakhmanov et al. | Feb 1993 | A |
5255741 | Alexander | Oct 1993 | A |
5265684 | Rosenhauch | Nov 1993 | A |
5271472 | Leturno | Dec 1993 | A |
5318137 | Johnson et al. | Jun 1994 | A |
5318138 | Dewey et al. | Jun 1994 | A |
5330016 | Paske et al. | Jul 1994 | A |
5332048 | Underwood et al. | Jul 1994 | A |
5348095 | Worrall et al. | Sep 1994 | A |
5368114 | Tandberg et al. | Nov 1994 | A |
5560440 | Tibbitts | Oct 1996 | A |
5590724 | Verdgikovsky | Jan 1997 | A |
5655609 | Brown et al. | Aug 1997 | A |
5788000 | Maury et al. | Aug 1998 | A |
5957222 | Webb et al. | Sep 1999 | A |
5957226 | Holte | Sep 1999 | A |
6059051 | Jewkes et al. | May 2000 | A |
6070677 | Johnston, Jr. | Jun 2000 | A |
6131675 | Anderson | Oct 2000 | A |
6189631 | Sheshtawy | Feb 2001 | B1 |
6209665 | Holte | Apr 2001 | B1 |
6213226 | Eppink et al. | Apr 2001 | B1 |
6244664 | Ebner et al. | Jun 2001 | B1 |
6269893 | Beaton et al. | Aug 2001 | B1 |
6289999 | Dewey et al. | Sep 2001 | B1 |
6360830 | Price | Mar 2002 | B1 |
6360831 | Åkesson et al. | Mar 2002 | B1 |
6378632 | Dewey et al. | Apr 2002 | B1 |
6419025 | Lohbeck et al. | Jul 2002 | B1 |
6427788 | Rauchenstein | Aug 2003 | B1 |
6464124 | Beaton et al. | Oct 2003 | B2 |
6668949 | Rives | Dec 2003 | B1 |
6732817 | Dewey | May 2004 | B2 |
20030079913 | Eppink et al. | May 2003 | A1 |
20030155155 | Dewey et al. | Aug 2003 | A1 |
20040065479 | Fanuel | Apr 2004 | A1 |
20040065480 | Fanuel et al. | Apr 2004 | A1 |
20040134687 | Radford et al. | Jul 2004 | A1 |
Number | Date | Country |
---|---|---|
1012545 | Dec 2000 | BE |
2 839 868 | Apr 1979 | DE |
0 086 701 | Aug 1983 | EP |
0 301 890 | Feb 1989 | EP |
0 577 545 | Mar 1993 | EP |
0 568 292 | Nov 1993 | EP |
569203 | Apr 1924 | FR |
218774 | Jul 1924 | GB |
295150 | Aug 1928 | GB |
540027 | Oct 1941 | GB |
1 586 163 | Mar 1981 | GB |
2 128 657 | May 1984 | GB |
2 180 570 | Apr 1987 | GB |
8 503 371 | Jul 1987 | NL |
WO 0031371 | Jun 2000 | WO |
WO 02072994 | Sep 2002 | WO |
Number | Date | Country | |
---|---|---|---|
20050241856 A1 | Nov 2005 | US |
Number | Date | Country | |
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Parent | PCT/BE2004/000057 | Apr 2004 | US |
Child | 11109350 | US |