This invention relates to construction systems using concrete panels.
Concrete panel systems have been used primarily to provide pre-manufactured walls for residential or small commercial or industrial buildings. Such systems promise a more accurate building, reduced on-site building time and waste, insect resistance and a hedge against rising lumber prices.
U.S. Pat. No. 3,475,529 describes a method of making a prestressed hollow core concrete panel. A first section is formed comprising a slab having a flat outer face and a plurality of ribs extending from an inner face. This first section is then laid ribs down on a second section, which is either a flat slab or a duplicate of the first section laid ribs up. The two sections are joined together. In an embodiment, the cores of the panel are closed.
U.S. Pat. No. 3,683,578 describes a concrete panel building system in which the panels have an inner insulating layer sandwiched between concrete layers. The space between the concrete layers cooperates with a guide nailed to a foundation to align the wall panels on the foundation. Upper portions of adjacent wall panels are secured together by a various bolted connections.
U.S. Pat. Nos. 4,605,529, 4,751,803 and 4,934,121 describe concrete wall panels having vertical ribs extending between horizontal upper and lower beams all attached to a concrete slab which provides the outer surface of the wall. The ribs and beams of the panels are reinforced by longitudinal reinforcing bars and the concrete slab is reinforced by a wire mesh. A “bolting saddle” cast into the ends of the upper beams allows adjacent panels to be bolted together. U.S. Pat. No. 5,656,194 describes an improved assembly jig having hinged sidewalls for use in making such panels.
U.S. Pat. No. 5,493,838 describes a method of constructing a basement from prefabricated concrete panels. The building site is first excavated and footings are positioned in the excavation to define the outline of the building. The footings have a groove in their upper surface to accept wall sections which comprise a slab having a flat outer face and a plurality of ribs on an inner face. Freestanding corner wall sections are placed first on the footings. Flat wall panels are then joined end-to-end between the corner sections to complete a peripheral wall. A conventional wooden floor deck is constructed over the peripheral wall to strengthen the structure before the basement is backfilled.
It is an object of the present invention to improve on the prior art. This object is met by the combination of features, steps or both found in the independent claims, the dependent claims disclosing further advantageous embodiments of the invention. The following summary may not describe all necessary features of the invention which may reside in a sub combination of the following features or in a combination with features described in other parts of this document.
In various aspects, the invention provides a concrete building panel having a slab and a plurality of ribs and beams. The ribs include interior ribs and end ribs which are generally perpendicular to the slab and oriented vertically in an installed panel. The beams include an upper and lower beam which are generally perpendicular to the slab and oriented horizontally in an installed panel.
The spacing of the ribs is determined in view if a fraction of the length or width of common sheet materials, the fraction having a numerator of 1 and a whole number denominator. A series of horizontal holes in the ribs are spaced at a selected constant spacing such that adjacent panels may be fastened together through them. Adjacent wall panels may be mounted with their bottom surfaces at different elevations, the elevations differing by the selected constant spacing.
A rabbet in the upper surface of the panel opens to the outside face of the panel to receive the exterior sheathing or finish material of a second wall panel mounted above the first wall panel. The second wall panel has an extension extending from its bottom surface into the rabbet of the lower wall panel. A smaller rabbet around some or all of the perimeter of the panel opens towards an outside face of the panel to receive water infiltration resisting material.
In one type of panel, the slab is separated from the ribs to provide an air gap. Reinforcing bar segments forming a series of at least partial triangles extend from the ribs to the slab to secure the slab in position relative to the ribs. Insulating blocks capable of resisting a compressive load are also provided between the slab and the ribs. The insulating blocks extend beyond the edges of the ribs to provide a surface for attaching sheet material between the ribs to close off the air gap.
Connections between holes in two adjacent concrete wall panels are made by a hollow conduit having an abutment at either end to engage the concrete wall panels. The abutments do not substantially block openings at the ends of the hollow conduit permitting materials to pass through the conduit. Preferably, the abutment on at least one end of the conduit is a nut threaded onto the conduit.
Other connections between adjacent panels involve horizontal channels in the exterior faces of the beams which extend from an edge of the panel to a hole through the beam. The horizontal channels of adjacent panels form a continuous channel. A stitch has a member which fits into the horizontal channels of two adjacent panels and legs which extend through the holes of the beams. The legs are adapted to receive a fastener to secure the stitch.
Other connections between adjacent panels involve vertical channels in the end ribs. The vertical channels of horizontally adjacent panels form a space. A plate is fitted into the space to provide an interference fit with the vertical channels to align the adjacent panels relative to each other. In some cases, the plate extends upwards into the space of a second pair of horizontally adjacent panels mounted on top of the first pair of horizontally adjacent panels.
Load bearing horizontal holes through the ribs are reinforced with reinforcing bar in the concrete arranged in generally triangular shapes. The load bearing holes and reinforcement are located such that apexes of the triangularly shaped reinforcement are located between the perimeter of the hole and the distal edge of the rib relative to the slab.
The concrete panels are made by providing a form having a base and sides which define the perimeter of the panel and sub-forms which define the space between the ribs. At least two sets of holes are made through the two opposed sides of the form and through two opposed sides of each sub-form. Each set of holes is concentric when the sub-forms are properly positioned in the form. The sub-forms are positioned in the form at least in part by placing rods through each set of concentric holes. Concrete is poured into the form to form the slab and the ribs. The rods are sized to produce holes in the ribs to accept the conduit connectors referred to above. The reinforcing bar is pre-assembled into a basket comprising wire mesh for the slab and trusses for the ribs.
By way of example, embodiments of the invention will be described with reference to the following figures.
a is a perspective view of the panel of
General Structure of Concrete Panels
The slab 12 is integrally connected to a top beam 18 and bottom beam 20 which extend from the inside face 16 of the slab 12. Beams 18, 20 are generally perpendicular to the slab 12 and are generally horizontal in an installed first panel 10. Beams 18, 20 are typically about 2.5 inches thick, the thickness varying with their expected loading. The slab 12 and beams 18, 20 are integrally connected to interior ribs 22 and end ribs 24 which also extend from the inside face 16 of the slab 12. Ribs 22, 24 have side surfaces 21 extending from and generally perpendicular to the slab 12 and are generally vertical in an installed first panel 10. Interior ribs 22 have centerlines 23 extending along their length midway between side surfaces 21 and are typically spaced apart at a spacing interval 25 to conveniently accommodate the attachment of whole sheets of common sheet materials 78, such as drywall or plywood, having standard length and width dimensions 78a and 78b respectively. End ribs 24 have distal side surfaces 21 and are typically spaced so that centerlines 23 of interior ribs 22 and distal side surfaces 21 of adjacent end ribs 24 are spaced apart at spacing interval 25. Spacing interval 25 is a fraction of one of the standard length and width dimensions 78a and 78b of common sheet materials 78, wherein the fraction has a numerator of 1 and a denominator equal to a whole number. For example, in countries where sheet materials 78 often have standard width dimensions 78b of four feet and standard length dimensions 78a of eight feet, the spacing interval 25 between the centerlines 23 of adjacent interior ribs 22 or between the centerline 23 of an interior rib 22 and the distal side surface 21 of an adjacent end rib 24 is typically ½, ⅓, or ¼ of 4 feet, which corresponds to 24, 16, or 12 inches, respectively. Alternatively, the spacing interval 25 could be based on the 8 foot dimension of the common sheet materials, providing a spacing interval 25 of, for example, ¼, ⅕, or ⅙ of 8 feet, which corresponds to 24, 19.2 or 16 inches. The ribs 22, 24 typically range from 1.5 to 2.5 inches in thickness depending on their expected loading.
The length of the first panel 10 is variable but limited by the equipment available to physically handle the first panel 10. For house construction, a standard first panel 10 is typically eight feet wide. For commercial or industrial construction where heavier cranes are likely available, standard first panels 10 may be 12 or 16 feet long. The height of a first panel 10 may also vary from a typical height of eight feet to ten feet or more for buildings with high ceilings. The width of a first panel 10 is typically ten inches for residential basements but may vary for particular applications. To simplify the following discussion, the first panel 10 will be assumed to be 8 feet long by 8 feet high by 10 inches thick and to have three interior ribs 22 and two end ribs 24 spaced to provide support for sheet materials every 24 inches. For first panels 10 of other basic dimensions or configurations, parts of the description below may be modified as required.
The upper surface of the top beam 18 preferably has a major rabbet 26 opening to the outside face 14 of the first panel 10. The major rabbet 26 is typically about 3.5 inches wide and 1.5 deep. The major rabbet 26 receives the exterior sheathing or finish material of an adjacent upper wall structure. This makes it difficult for water running down that sheathing or finish material to enter the building by flowing across the upper surface of the top beam 18. The first panel 10 is also surrounded by a minor rabbet 28 (best shown in
The tops and bottoms of the end ribs 24 preferably include a widened portion 30 extending into the beams 18, 20. This widened portion 30 provides space for increased interior metal reinforcement as well as more concrete to strengthen the corners of the first panel 10.
The ribs 22, 24 are each provided with an equal number of horizontal holes 32 located at substantially the same elevations. These horizontal holes 32 have an appreciable diameter, typically about two and one eighth inches. As will be discussed further below, the horizontal holes 32 are used to attach a first panel 10 to an adjacent wall panel and at least one horizontal hole 32 preferably extends through each widened portion 30. The horizontal holes 32 also provide space to run electrical wiring or plumbing etc. through first panels 10. The vertical spacing of the horizontal holes 32 is preferably determined as follows. A nominal spacing is selected which gives an acceptable number of horizontal holes 32. A first hole, which can be the highest or lowest horizontal hole 32, is located so that its centre is at least a few inches from the closest beam 18, 20 and the centre of a last whole will also be at least a few inches from the closest beam 18, 20. Other horizontal holes 32 are placed with their centres at a multiple of the nominal spacing from the first hole. For example, an first panel eight feet high typically has horizontal holes 32 located at one foot, three feet, five feet and seven feet from the top or bottom of the first panel 10.
The end ribs 24 have vertical channels 34 in their outer sides preferably extending along their entire length. The vertical channels 34 cross the faces of the horizontal holes 32. The vertical channels 34 are typically about ¼ inch deep and four inches wide. The vertical channels 34 continue into horizontal channels 36 in the upper surfaces of the top beam 18 and, optionally, the lower surfaces of the bottom beam 20. The horizontal channels 36 are typically narrower than the vertical channels 34. The horizontal channels 36 extend from the vertical channels 34 to a proximal vertical hole 38.
Other vertical holes 38 are also provided in the beams 18, 20. These vertical holes 38 may be of the same size as the horizontal holes 32 and serve a similar purpose. An exception, however, is vertical holes 38 in a beam 18, 20 that do not intersect a horizontal channel 36 and are not used to provide a conduit for services. Such vertical holes 38 may be of a smaller diameter and may be located on different spacings. Vertical holes 38 may be used to attach a first panel 10 to a foundation or other building element.
The first panel 10 typically rests on a footing 40.
In general, the second panel 50 may be sized and reinforced unlike the first panel 10 as required by the loading on an above grade wall as compared to a basement wall. The bottom beam 20 may be made wider than required for strength, however, to distribute the weight of the second panel 50 particularly when a second panel 50 will be installed on a wood floor deck. The second panel 50 also has an extension 52 which protrudes from the lower surface of the bottom beam 20 extending the outside face 14 of the second panel 50 downwards. This extension 52 is sized to fit into the major rabbet 26 of a lower first panel 10 or second panel 50. Where a floor deck is mounted on the lower first panel 10 or second panel 50, the extension 52 is longer than shown in
The third panel 60 has an air gap 62 between the slab 12 and the beams 18, 20 and ribs 22, 24. The air gap 62 acts as a thermal break, a capillary break and as a channel to allow water or water vapour to flow out of the wall. The beams 18, 20 and ribs 22, 24 are spaced from the slab 12 by insulating blocks 64 which are arranged or drilled to provide passages across ribs 22, 24 (including ribs of adjacent third panels 60) and, in some applications, across beams 18, 20 (not illustrated). A preferred material for the insulating blocks 64 is a composite of polyethylene and cellulose or wood flour which is non-rusting, insulating and strong in compression such as POLYBOARD™, sold by Renew Resources of Toronto, Ontario, Canada.
The beams 18, 20 and ribs 22, 24 are connected to the slab 12 by metal reinforcement which will be described further below. The insulating blocks 64 preferably surround any metal reinforcement crossing the air gap 62 to inhibit condensation and rusting. Optionally, reinforcement that crosses the air gap 62 can be treated to prevent rusting, for example, by coating it with epoxy. Inner sheets 70, typically plywood or oriented strand board, extend between adjacent insulating blocks 64. The inner sheets 70 keep insulation placed between ribs 22, 24 out of the air gap 62 and may also support vapour or water barriers as required. The structure of the third panel 60 thus resembles many of the feature of a conventional stud wall with masonry facing.
Like the second panel 50, the third panel 60 has an extension 52 which protrudes from the lower surface of the bottom beam 20 and extends the outside face 14 of the third panel 60 downwards. The extension 52 of the third panel 60 is similarly sized to fit into the major rabbet 26 of a lower first panel 10 or second panel 50 but the extension 52 is not as thick as a major rabbet 26 so that the air gap 62 will be in fluid communication with a major rabbet 26.
The description of the panels 10, 50, 60 above relates primarily to standard sized panels. Since most buildings are not sized as even multiples of the width of standard panels 10, 50, 60, custom panels are made as required by making suitable modifications to the description above. Similarly, modified panels are made for corners. The following description applies to corners made of any of the panels 10, 50, 60 discussed above.
Connections Between Concrete Panels and Other Building Elements
The connection is completed by inserting pipe bolts 92 through the horizontal holes 32 and plate holes 98 and tightening them. Typically, a pipe bolt 92 is fastened through each horizontal hole 32 of adjacent end ribs 24 and optionally through each vertical hole 38 of vertically adjacent beams 18, 20 (not illustrated). The pipe bolts 92 consist of a section of hollow pipe 100, typically steel, of about two inches in outside diameter. The horizontal holes 32 are preferably slightly larger in diameter (ie. by about one eight of an inch) than the pipe 100 to permit a small amount of adjustment between panels 10, 50, 60 or to compensate for slight misalignment of the panels 10, 50, 60.
The pipe 100 is drilled to receive a pin 102 at one end and threaded on its other end to receive a nut 104. Alternatively, the pipe 100 may be threaded on both ends and have two nuts 104. In either event, tightening at least one nut 104 draws adjacent panels 10, 50, 60 together. Because the pipes 100 are hollow, however, wire or conduits can still be passed through horizontal holes 32 or vertical holes 38. The pipe 100 also presents more surface area in contact with the end ribs 24 than would a typical bolt and thus reduces the possibility the a force applied between the pipe 100 and an end rib 24 or beam 18, 20 crushes the concrete around a hole 32, 38.
In addition to or in place of the plate 96, a stitch 108 can be used to attach horizontally adjacent panels 10, 50, 60. As shown in
The upper member 110 of the stitch 108 fits into the horizontal channels 36 of adjacent panels 10, 50, 60. The legs 112 extend through vertical holes 38 in the beams 18, 20. Stitch nuts 114 are then threaded onto the legs 112 and tightened. Depending on the application, stitches 108 may be used on the bottom beams 20, top beams 18 or both of adjacent panels 10, 50, 60.
When a stitch 108 is used without a plate 96, the stitch 108 performs the function of keeping panels 10, 50, 60 aligned while pipe bolts 92 are being fastened. This allows, as an alternative to the arrangement shown in
The connections of
Methods of Making Concrete Panels and Their Interior Structure
The perimeter of the form 132 consists of a base 134, first sides 136 and second sides 138. For small runs, the base 134 and sides 136, 138 are preferably made of wood and nailed together with double headed nails for easier form stripping after a panel 10, 50 is made. For production runs, the base 134 and sides 136, 138 are preferably made of steel and attached with releasable clips 140. A plurality of sub-forms 142 define the interior edges of the beams 18, 20 and ribs 22, 24. The sub-forms 142 are bottomless, however, and do not form the inside face 16 of the slab 12.
The first sides 136 are provided with side holes 144 spaced relative to the ribs 22, 24 so as to be concentric with the horizontal holes 32. A rod 146, typically a hollow steel pipe, has an outside diameter substantially equal to the diameter of the horizontal holes 32. The sub-forms 142 have sub form holes 148 which receive the rods 146 when the sub-forms 142 are in their proper position relative to the form 132. The rod 146 passes through the side holes 144 and sub-form holes 148 and extends across the form 132. Clamps 150 secure the sub-forms 142 in place laterally.
The sub-forms 142 are placed in the form 132 and the rods 146 are slid in place. The rods 146 act as a jig to quickly locate and hold the sub forms 142 in their proper place. Clamps 150 are secured. A layer of concrete to make the slab 12 is placed in the bottom of the form 132 (it can be poured through the sub-forms 142) and allowed to set somewhat so that it will not be substantially dislocated by later steps. More concrete is added to the form 132 to fill the spaces around the sub-forms 142. When the form 132 is filled, the concrete may vibrated as required and its exposed surface finished. Some special features, such as the return 88 shown in
The arrangement of the form 132 described above allows a textured base 134 to be used which applies an architectural finish to the outside face 14 of the slab 12. Alternatively, the sub-forms 142 can be inverted and positioned to contact the base 134. In this orientation, the outside face 14 of the slab 12 faces upwards and is exposed during forming. Such an exposed outside face 14 can be finished, for example, by texturing it or casting half bricks or tiles into it. In this orientation, the base 134 can also be made of a suitable sheet material with nails or other connectors protruding into the beams 20, 22 or ribs 22, 24. This sheet material remains a part of the panel 10, 50 after the concrete cures.
After the concrete cures, the form 132 is stripped, the components having previously been coated with release compound to make stripping easier. The rods 146 are removed by pulling them sideways out of the form 132. Because of the location and size of the rods 146, removing them automatically creates horizontal holes 32 where required. Vertical holes 38 are preferably also created during forming, for example by leaving sacrificial spacers in the form 132 as is known in the art. The sub-forms 142 have rings 152 which receive a cable from an overhead crane which pulls them out. The sub-forms 142 are preferably made of spring steel so that they flex away from the concrete when pulled to make stripping easier. The sides 136 and 138 are then separated from the base 134.
Optionally, the sub-forms 142 can be made of rigid foam insulation. In that case, the sub-forms 142 are not stripped and remain in the panel 10, 50 except as required to accommodate pipe bolts 92. Such foam sub-forms 142 are particularly useful when a return 88 (as shown in
The description above also applies to a third panel 60, but with some modifications. Before any concrete is poured or after the concrete for the slab 12 is poured, sub-forms 142 are located in the form 132 by rods 146 and clamps 150. Insulting blocks 64 are attached to the lower edges of the sides of the sub-forms 142. The insulting blocks 64 are cut or shaped as necessary to accommodate reinforcing material extending from the slab 12 of ribs 22, 24 or beams 18, 20 and provide passages 66 as discussed above. Additional material is also attached to the lower edges of the sides of the sub-forms 142 to temporarily fill the passages 66. This material will be removed later and is preferably a soft foam. Concrete for the slab 12 is then poured through the sub-forms 142 and vibrated in place. Concrete for the beams 18, 20 and ribs 22, 24 is then poured into the spaces between the sub-forms 142. After the concrete cures, the form 132 is stripped and the additional material removed. Inner sheets 70 may be added to the third panel 60 and attached to the insulating blocks 64 while the concrete is curing or after casting of the entire panel.
As was mentioned above, the panels 10, 50, 60 are reinforced. Preferably, this reinforcing is pre-formed in a basket 160 as shown in
Diagonals 174 run across the cords 168, 170, 172 and are welded to them. Although the diagonals 174 may be distinct pieces, several diagonals 174 are typically made simultaneously by bending a piece of steel as required. The intersections 176 of the diagonals 174 at the upper cord 168 are spaced as described for the horizontal holes 32. Thus, as shown in
It is to be understood that what has been described are preferred embodiments of the invention. The invention nonetheless is susceptible to certain changes and alternative embodiments without departing from the subject invention, the scope of which is defined in the following claims.
Number | Date | Country | Kind |
---|---|---|---|
2240098 | Jun 1999 | CA | national |
2274287 | Jun 1999 | CA | national |
This application is a continuation of U.S. application Ser. No. 10/752,583, filed Jan. 8, 2004, which is a continuation of U.S. application Ser. No. 09/705,788, filed Nov. 6, 2000, issued as U.S. Pat. No. 6,698,150, which is a continuation of International Application No. PCT/CA00/00697, filed Jun. 9, 2000, and a continuation-in-part of U.S. application Ser. No. 09/328,901, filed Jun. 9, 1999, issued as U.S. Pat. No. 6,260,320. All of the patents and applications listed above are incorporated herein, in their entirety, by this reference to them.
Number | Name | Date | Kind |
---|---|---|---|
2043697 | Deichmann | Jun 1936 | A |
2202745 | Muse | May 1940 | A |
RE21905 | Nielsen | Sep 1941 | E |
2262899 | Mechlin | Nov 1941 | A |
2270846 | Hines | Jan 1942 | A |
2321813 | Henzel | Jun 1943 | A |
2515977 | Banneyer | Jul 1950 | A |
3232018 | MacKean | Feb 1966 | A |
3281510 | Lovret | Oct 1966 | A |
3475529 | Lacy | Oct 1969 | A |
3683578 | Zimmerman | Aug 1972 | A |
3885369 | Ott | May 1975 | A |
3959940 | Ramberg | Jun 1976 | A |
3979863 | Hurley | Sep 1976 | A |
4019293 | Armas | Apr 1977 | A |
4030262 | Dean | Jun 1977 | A |
4112646 | Clelland | Sep 1978 | A |
4157640 | Joannes | Jun 1979 | A |
4178343 | Rojo, Jr. | Dec 1979 | A |
4182092 | Weaver | Jan 1980 | A |
4211043 | Coday | Jul 1980 | A |
4219978 | Brown | Sep 1980 | A |
4320606 | GangaRao | Mar 1982 | A |
4336676 | Artzer | Jun 1982 | A |
4454702 | Bonilla-Lugo et al. | Jun 1984 | A |
4530191 | Boisbluche | Jul 1985 | A |
4554124 | Sudrabin | Nov 1985 | A |
4570398 | Zimmerman | Feb 1986 | A |
4605529 | Zimmerman | Aug 1986 | A |
4611450 | Chen | Sep 1986 | A |
4614013 | Stevenson | Sep 1986 | A |
4669240 | Amormino | Jun 1987 | A |
4731915 | Holder | Mar 1988 | A |
4751803 | Zimmerman | Jun 1988 | A |
4759160 | Fischer | Jul 1988 | A |
4781006 | Haynes | Nov 1988 | A |
4901491 | Phillips | Feb 1990 | A |
4934121 | Zimmerman | Jun 1990 | A |
4998393 | Baena | Mar 1991 | A |
5055252 | Zimmerman | Oct 1991 | A |
5058345 | Martinez | Oct 1991 | A |
5183616 | Hedrick | Feb 1993 | A |
5222338 | Hull et al. | Jun 1993 | A |
5317848 | Abbey | Jun 1994 | A |
5335472 | Phillips | Aug 1994 | A |
5381635 | Sanger | Jan 1995 | A |
5398470 | Ritter et al. | Mar 1995 | A |
5493838 | Ross | Feb 1996 | A |
5501055 | Storch et al. | Mar 1996 | A |
5566520 | Branitzky | Oct 1996 | A |
5656194 | Zimmerman | Aug 1997 | A |
5865001 | Martin et al. | Feb 1999 | A |
5950390 | Jones | Sep 1999 | A |
5953864 | Beck | Sep 1999 | A |
6003278 | Weaver et al. | Dec 1999 | A |
6112498 | Hansson et al. | Sep 2000 | A |
6151843 | Weaver et al. | Nov 2000 | A |
6260320 | Di Lorenzo | Jul 2001 | B1 |
6338231 | Enriquez | Jan 2002 | B1 |
6401417 | Leblang | Jun 2002 | B1 |
6427406 | Weaver et al. | Aug 2002 | B1 |
6463702 | Weaver et al. | Oct 2002 | B1 |
6698150 | Di Lorenzo | Mar 2004 | B1 |
Number | Date | Country |
---|---|---|
2078381 | Sep 1992 | CA |
20 17 109 | Nov 1970 | DE |
22 54 174 | May 1974 | DE |
29 51 898 | Jul 1980 | DE |
34 13 305 | Oct 1984 | DE |
0 818 287 | Jan 1998 | EP |
483834 | May 1917 | FR |
863026 | Mar 1931 | FR |
898765 | Jul 1944 | FR |
1422473 | Mar 1966 | FR |
2045625 | Mar 1971 | FR |
2 560 621 | Sep 1985 | FR |
1 119 057 | Nov 1965 | GB |
10252278 | Sep 1998 | JP |
Number | Date | Country | |
---|---|---|---|
20060185290 A1 | Aug 2006 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 10752583 | Jan 2004 | US |
Child | 11389316 | US | |
Parent | 09705788 | Nov 2000 | US |
Child | 10752583 | US | |
Parent | PCT/CA00/00697 | Jun 2000 | US |
Child | 09705788 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 09328901 | Jun 1999 | US |
Child | PCT/CA00/00697 | US |