SYSTEM AND METHOD FOR PREVENTING CRACKS IN STRUCTURAL CONCRETE

Abstract

A system and method for preventing cracks in structural concrete associated with a building structure, the building structure having one or more wooden support columns. Each wooden support column has a base supported by a ground surface and is provided with a crack prevention member having a first, upper or top surface and a second, lower or bottom surface; an outer side wall; and an inner side wall defining a cut-out portion; the base of the wooden support beam is positioned within the cut-out portion. A concrete floor is poured on the ground surface no higher than the level of the first, upper surface of the crack prevention member, and no floor concrete or other structural concrete contacts the wooden support column. The crack prevention member may comprise various materials including rubber, plastic, resin, or other polymeric material and combinations thereof.

Claims

1. A system for preventing cracks in structural concrete associated with a building structure, the building structure having at least one wooden support column for supporting a portion of the building structure above a concrete floor, the wooden support column having a base supported by a ground surface underneath the building structure, the system comprising: at least one crack prevention member having a first surface, a second surface, an outer side wall, and an inner side wall defining a cut-out portion, the base of the wooden support column being positioned within said cut-out portion of said crack prevention member; wherein the concrete floor is poured to a level such that the floor concrete only contacts said outer side wall of said crack prevention member and does not contact the wooden support column; further wherein no other structural concrete contacts the wooden support column; and wherein said crack prevention member remains in the concrete floor after the concrete floor has set.

2. The system for preventing cracks in structural concrete associated with a building structure of claim 1, wherein said crack prevention member has a polygonal shape and comprises a first outer side wall, a second outer side wall, and a third outer side wall.

3. The system for preventing cracks in structural concrete associated with a building structure of claim 2, further wherein said crack prevention member is configured to be separable at a separation region where said first outer side wall connects to said second outer side wall.

4. The system for preventing cracks in structural concrete associated with a building structure of claim 3, wherein said crack prevention member is separable by at least one of flexing said first outer side wall and said second outer side wall at said separation region, and cutting at least partially through said separation region.

5. The system for preventing cracks in structural concrete associated with a building structure of claim 1, wherein said cut-out portion has a polygonal shape.

6. The system for preventing cracks in structural concrete associated with a building structure of claim 5, wherein the base of the wooden support column has a polygonal shape that is the same as the polygonal shape of said cut-out portion.

7. The system for preventing cracks in structural concrete associated with a building structure of claim 6, wherein the shape and dimensions of said cut-out portion are substantially similar to the shape and dimensions of the base of the wooden support column.

8. The system for preventing cracks in structural concrete associated with a building structure of claim 1, wherein said crack prevention member comprises at least one of a rubber, plastic, resin, or other polymeric material.

9. The system for preventing cracks in structural concrete associated with a building structure of claim 6, wherein each side of the base of the wooden support column that is not adjacent a wall of the building structure is adjacent said inner side wall of said crack prevention member.

10. The system for preventing cracks in structural concrete associated with a building structure of claim 1, wherein at least one saw cut is provided in the concrete floor, at least one end of said saw cut terminating adjacent a corner of said crack prevention member.

11. A system for preventing cracks in structural concrete associated with a building structure, the building structure having a plurality of wooden support columns for supporting the building structure, each wooden support column having a base supported by a ground surface underneath the building structure, the system comprising: at least one crack prevention member having a first surface, a second surface, an outer side wall, and an inner side wall defining a cut-out portion, the base of each wooden support column being positioned within said cut-out portion of said crack prevention member; wherein the shape and dimensions of said cut-out portion are substantially similar to the shape and dimensions of the base of the wooden support column positioned within said cut-out portion; further wherein no structural concrete contacts the wooden support column.

12. The system for preventing cracks in structural concrete associated with a building structure of claim 11, wherein said crack prevention member has a polygonal shape.

13. The system for preventing cracks in structural concrete associated with a building structure of claim 11, wherein said cut-out portion has a polygonal shape.

14. The system for preventing cracks in structural concrete associated with a building structure of claim 13, wherein the base of each wooden support column has a polygonal shape that is the same as the polygonal shape of the cut-out portion that the base is positioned within.

15. The system for preventing cracks in structural concrete associated with a building structure of claim 11, wherein the crack prevention member comprises at least one of a rubber, plastic, resin, or other polymeric material.

16. The system for preventing cracks in structural concrete associated with a building structure of claim 11, wherein each side of the base of each wooden support column that is not adjacent a wall of the building structure is adjacent an inner side wall of said crack prevention member.

17. The system for preventing cracks in structural concrete associated with a building structure of claim 11, wherein at least one saw cut is provided in the concrete floor, at least one end of said saw cut terminating adjacent a corner of the crack prevention member.

18. A method for preventing cracks in a concrete floor associated with a building structure positioned atop a ground surface, the building structure having a plurality of wooden support columns for supporting the building structure, each wooden support column having a base and at least three sides, said method comprising: aligning each of a plurality of crack prevention members with the base of a corresponding wooden support column, each crack prevention member having a first surface, a second surface, a first outer side wall, a second outer side wall, a corner formed by the first outer side wall and the second outer side wall, and an inner side wall defining a cut-out portion; each cut-out portion having the same shape as the base of its corresponding wooden support column and dimensions substantially similar to the dimensions of such base; said aligning comprising causing the base of each wooden support column to extend through the cut-out portion such that each base is supported by the ground surface; pouring concrete, including to form a concrete floor, such that no structural concrete contacts the wooden support column; allowing the concrete floor to set; providing at least one saw cut in the concrete floor, at least one end of the saw cut terminating adjacent the corner of the crack prevention member; wherein each side of the base of each wooden support column that is not adjacent a wall of the building structure is adjacent the inner side wall of the crack prevention member defining the cut-out portion through which the base extends.

19. The method for preventing cracks in structural concrete associated with a building structure of claim 18, wherein the crack prevention member remains in the concrete floor after the concrete has set.

20. The method for preventing cracks in structural concrete associated with a building structure of claim 18, wherein each base and the cut-out portion through which the base extends have the same shape and substantially the same dimensions.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 shows an example of cracking that may occur in concrete floors associated with a building structure.

[0021] FIG. 2 shows one embodiment of a system for preventing cracks in a concrete floor of a building structure.

[0022] FIGS. 3A and 3B show a system for preventing cracks in a concrete floor of a building structure, including a perspective view of a crack prevention member.

[0023] FIGS. 4A and 4B provide respective top views of two crack prevention members with two cut-out portions that vary with respect to geometric shape.

[0024] FIGS. 5A and 5B provide plan views of a concrete floor of a building structure with crack prevention members in place.

[0025] FIG. 6 shows an alternative embodiment of a crack prevention member.

[0026] FIGS. 7A through 7C show further embodiments of a crack prevention member.

[0027] FIG. 8 shows another embodiment of a system for preventing cracks in a concrete floor of a building structure.

[0028] FIG. 9 shows a further embodiment of a system for preventing cracks in a concrete floor of a building structure.

[0029] FIG. 10 shows a yet further embodiment of a system for preventing cracks in a concrete floor of a building structure.

DETAILED DESCRIPTION

[0030] Referring to FIG. 1, the figure shows a concrete floor that has undergone cracking caused for example by shrinkage, frost heave, or excessive weight. Cracking in concrete is not only aesthetically unappealing, but may also compromise the structural integrity of a patio, garage, or other building structure associated with the concrete floor. In particular, where the cracks appear around a wooden support column as shown, this may weaken the wooden support column's weight-bearing capacity and lead to building code violations and/or safety concerns.

[0031] For purposes of the present description, wooden support column and terms similar to column such as pole, post, and beam, refer to a wooden, vertical, load-bearing construction element having a base whose bottom surface is supported by the ground without being secured, attached, or affixed to another construction element intended to limit movement of the wooden support column, such as a concrete pad or base plate. The phrases on the ground, on the ground surface, supported by a ground surface, and the like similarly means that the base and bottom surface of the wooden support column are not secured, attached, or affixed to another construction element intended to prevent or limit movement of the wooden support column, such as a concrete pad or base plate; it does not necessarily mean that the bottom surface of the wooden support column is in direct contact with or embedded in the ground or dirt, though such direct contact and embedding are within the present scope. References to structural concrete mean concrete that is deliberately added to the building structure to provide a structural function. A structural function may be to bear a load; provide a foundation, such as a concrete floor; or provide another structural feature such as concrete steps or stairs. Structural concrete does not mean concrete that is present by incidental or accidental means, such as concrete that may splash where it is not intended during pouring, or that may drip off a trowel, or be deposited by a hand or glove that has concrete on it.

[0032] In addition, statements herein to the effect that no structural concrete contacts the wooden support column mean that no concrete having a structural function in the building structure contacts the base of the wooden support column during the construction process. It is to be expected that during the process of construction some concrete may incidentally contact the wooden support column, such as by splashing or splattering, and such incidental contact of concrete with the support column does not negate the characterizations here to the effect that no structural concrete contacts the base of the wooden support column.

[0033] In construction where wooden support columns are used, the base of the wooden support column may rest on the ground and be subject to vertical movement in response to movement of the ground surface on which the base rests. Such movement of the ground may be caused, for example, by changes in ground temperature, by subsidence of the underlying ground, by upward movement of the ground such as in response to increased moisture content, and/or by changes in the load being supported by the wooden support column. In cold climates, freezing and/or thawing of the ground can cause the ground under the base of the wooden support column to rise and/or sink. For example, freezing of the ground can cause the ground contacting the bottom surface of the base of a wooden support column to move upwards, such as in a frost heave, causing the base of the wooden support column to also move upwards. Similarly, thawing or subsidence of the ground supporting the base of the wooden support column may cause the ground under the base of the wooden support column to move downwards, causing the base of the wooden support column to also move downwards. In addition, a wooden support column bearing a certain load may move upward if the weight of the load is decreased, or may move downward if the weight of the load is increased. In any situation causing vertical movement of the wooden support column, if the wooden support column is rigid contact with any concrete, directly or otherwise, and whether floor concrete or other concrete, the movement of the wooden support column may cause damage to the concrete, such as by cracking the concrete, and/or may cause damage to the wooden support column.

[0034] FIG. 2 shows a system for preventing cracks in a concrete floor 12 of a building structure 14. The system includes a plurality of wooden support columns 18, each positioned within a crack prevention member 10. Each wooden support column 18 has a base 18a embedded within or resting on ground surface 16. Ground surface 16 is located underneath building structure 14 and concrete floor 12, which is positioned atop ground surface 16. A top end 18b of wooden support column 18 is positioned adjacent an upper building layer, shown here as roof 19, of building structure 14. Each crack prevention member 10 includes a first surface 10a, a second surface 10b, at least two outer side walls 10c-10d, and at least one inner side wall 10e-10g, as well as a cut-out portion 15. The base 18a of each wooden support column 18 is positioned within a cut-out portion 15. Wooden support column 18 and crack prevention member 10 may be positioned adjacent an outer skirt board 21 of building structure 14, which is placed along a lower wall of building structure 14. Skirt board 21 typically runs about 2-4 inches in depth and about 12 inches in height. Two or more kicker studs 23 may extend at an angle from each wooden support column 18, for providing supplementary bracing to wooden support column 18 and building structure 14. Each wooden support column 18 may be a treated wooden post of any suitable size, including but not limited to a 66 inch treated post.

[0035] Crack prevention member 10 may have a rectangular, square, triangular or other polygon shape, and is typically made from rubber, plastic, resin, or other similar polymeric material as well as combinations thereof. The polymeric material of crack prevention member 10 may further include metal, graphite, ceramic, or other similar substances, which enhance the toughness and thermal properties of crack prevention member 10. Outer side walls 10c-10d and inner side walls 10e-10g of crack prevention member 10 may be about 2 to 6 inches in height. When concrete floor 12 is under construction, concrete is poured to a level such that the concrete contacts outer side walls 10c-10d of crack prevention member 10, but neither the floor concrete nor any other structural concrete contacts wooden support column 18.

[0036] FIG. 3A shows how crack prevention member 10 may be fastened to an outer skirt board 21. In particular, outer side walls 10c-10d of crack prevention member 10 may be fastened to outer skirt board 21 via a fastening member 24. Fastening member 24 may be for example one or more bolts, pins, screws, nails, studs, or other similar fastening member known in the art. FIG. 3B is a perspective view of crack prevention member 10 showing outer side walls 10c-10d, inner side walls 10e-10g, and cut-out portion 15. In particular, FIG. 3B shows that cut-out portion 15 extends through first surface 10a and second surface 10b of crack prevention member 10 thereby exposing inner side walls 10e-10g. As shown in FIG. 3B, cut-out portion 15 has three sides coinciding with inner side walls 10e-10g and a fourth side 15a, which is open. This fourth open side 15a, facilitates the insertion of wooden support column 18 within cut-out portion 15. The base 18a of each wooden support column 18 may have a shape including square, rectangular, triangular, or other polygon shape. Similarly, cut-out portion 15 may have a shape and dimensions substantially similar to base 18a of each wooden support column 18. In the context of the relationship between the shape and dimensions of base 18a and cut-out portion 15, substantially similar means that base 18a substantially fills, without exceeding the dimensions of, cut-out portion 15. In other words, base 18a must be fully within cut-out portion 15, and should have the same shape and dimensions as cut-out portion 15 within the constraints of normal construction processes and tolerances.

[0037] FIGS. 4A and 4B provide respective perspective and top views of crack prevention member 10. In particular, FIG. 4A shows crack prevention member 10 including outer side walls 10c-10d. Wooden support column 18 is positioned within cut-out portion 15 and may have a base 18a of any size and shape as long as the size and shape of base 18a correspond to the size and shape of the cut-out in corresponding crack prevention member 10. Here, wooden support column 18 is square-shaped measuring approximately 5-7 inches on each side thereof. In FIG. 4B, a rectangular wooden support column 18 is illustrated. As with the example shown in FIG. 4A, the sides of cut-out portion 15 may be any size as long as the dimensions of cut-out portion 15 coincides with the dimensions of wooden support column base 18a. FIGS. 4A and 4B also show each crack prevention member 10 may also include chalk line head holder 25. Chalk line head holder 25 allows attachment of a chalk line to each crack prevention member 10 in order to facilitate proper alignment of each crack prevention member 10 as well as a plurality of saw cuts 28 as discussed below.

[0038] FIGS. 5A and 5B provide area views of concrete floor 12 having crack prevention members 100 distributed thereon. Concrete floor 12 is utilized as part of a building structure 14 such as a garage, which may include a plurality of planar side walls 30. In particular, FIG. 5A shows crack prevention member 100a may be positioned adjacent a planar side wall 30a. In addition, crack prevention member 100b may be positioned where two planar side walls 30a meet forming a corner 30b, and crack prevention member 100c may be positioned near a doorway 30c of the building structure. Each crack prevention member 100 includes cut-out portion 15 with a wooden support column (not shown) positioned therein. Each wooden support column is embedded in ground surface 16 below concrete floor 12 in order to support the weight of the building structure 14. FIG. 5B shows that when a wooden support column 18 is positioned adjacent planar side wall 30a of a building structure, that at least two corners 18c and 18d of the wooden support column 18 lie adjacent two straight sides of crack prevention member 100. In contrast, when a wooden support column 18 is positioned in a corner 30b of building structure 14, at least one corner 18e thereof lies adjacent at least one straight side of crack prevention member 100. FIGS. 5A and 5B also show concrete floor 12 having a plurality of saw cuts 28. As shown in FIG. 5A, saw cuts 28 are cut into the concrete of concrete floor 12. Saw cuts 28 extend from a pointed edge 11a of a first crack prevention 100 to pointed edge 11b of a second crack prevention member 100 located directly opposite first crack prevention member 100. The purpose of saw cuts 28 is to alleviate stress and provide a further means of preventing random cracks of concrete floor 12.

[0039] FIG. 6 shows an alternative embodiment of a crack prevention member 200. In particular, crack prevention member 200 of FIG. 6 may be utilized in a central portion of a concrete floor 12. FIG. 6 contemplates three different embodiments of centrally-located crack prevention member 200. In a first embodiment, crack prevention member 200 may have the shape of two equilateral triangles, each having a rectangular cut-out portion 15 cut therein. In this embodiment, when the base of each equilateral triangle are positioned adjacently, a single square-shaped cut-out portion 15 results. In a second embodiment, four equilateral triangles are assembled so as to surround wooden support column 180. Two of the four triangles may be of one size and the other two triangles may be of a different size.

[0040] As shown in FIG. 6, wooden support column 180 is positioned such that each corner 180a-180d of wooden support column 180, lies adjacent a straight side of crack prevention member 200. In addition, as in FIGS. 5A and 5B, saw cuts 28 are cut into the concrete of concrete floor 12 after the concrete has set. Each saw cut 28 emanates from each pointed edge 11 of crack prevention member 200 in order to control cracking of concrete floor 12.

[0041] The present crack prevention system also contemplates a method for preventing cracks in a concrete floor 12 associated with a building structure 14. FIG. 2 shows concrete floor 12 of a building structure 14. Each wooden support column 18 is embedded near its base 18a within ground surface 16. Ground surface 16 is located underneath building structure 14 and concrete floor 12, which is positioned atop ground surface 16. A top end 18b of wooden support column 18 is positioned adjacent a roof 19 of building structure 14.

[0042] The first step in the method of preventing cracks in a concrete floor involves placing a plurality of crack prevention members 10 at various positions on a ground surface 16. Each crack prevention member 10 includes first, upper or top surface 10a and second, lower or bottom surface 10b; at least two outer side walls 10c-10d; and at least one inner side wall 10e-10g, as well as a cut-out portion 15. The second step entails placing the base 18a of each wooden support column 18 within the cut-out portion 15 of each crack prevention member 10 and into the ground surface 16 such that each wooden support column 18 is embedded into ground surface 16. Wooden support column 18 and crack prevention member 10 may be positioned adjacent an outer skirt board 21 of building structure 14, which is placed along a lower wall of building structure 14. Outer skirt board 21 typical runs about 2-4 inches in depth and about 12 inches in height. Two or more kicker studs 23 may extend at an angle from each wooden support column 18, for providing supplementary bracing to wooden support column 18 and building structure 14. Each wooden support column 18 may be a treated wooden post, such as a 66 inch post or any other suitable size.

[0043] A further step in the method as shown in FIG. 5A involves positioning crack prevention members 100a adjacent planar side walls 30a, positioning crack prevention members 100b where two planar side walls 30a meet forming corner 30b, and positioning crack prevention members 100c near a doorway 30c of building structure 14. Each type of crack prevention member 100 includes cut-out portion 15 with a wooden support column (not shown) positioned therein. Each wooden support column 18 is embedded in ground surface 16 below concrete floor 12 in order to support the weight of the building structure 14.

[0044] The next step in the method is illustrated in FIG. 5B. When wooden support column 18 is positioned adjacent planar side wall 30a of a building structure, wooden support column 18 is positioned such that at least two corners 18c and 18d thereof lie adjacent two straight sides of crack prevention member 100. In contrast, when a wooden support column 18 is positioned in a adjacent at least one straight side of crack prevention member 100.

[0045] Next, concrete is poured to a level such that concrete contacts the outer side walls of crack prevention member 100, but concrete does not contact wooden support columns 18. Following this step, the concrete is allowed to set. Once the concrete has cured, the concrete contacts the outer side walls of crack prevention member 100, but the concrete does not contact any part of the wooden support columns 18.

[0046] A final step in the method is shown in FIG. 5A. A plurality of saw cuts 28 are cut into the concrete of concrete floor 12 subsequent to its curing. Saw cuts 28 extend from a pointed edge 11a of a first crack prevention member 100 to pointed edge 11b of a second crack prevention member 100 located directly opposite from first crack prevention member 100. Saw cuts 28 alleviate stress and provide a further means of preventing random cracks of concrete floor 12.

[0047] The crack prevention member may be provided with one or more separation regions that allow the device to be separated into component portions. FIG. 7A shows crack prevention member 10 including first surface 10a, second surface 10b, outer side walls 10c and 10d, first triangular crack prevention member portion 10j, second triangular crack prevention member portion 10k, and third triangular crack prevention member portion 10l. As shown in FIG. 7A, separation regions 10h and 10i are present at the inside corners of cut-out portion 15 of crack prevention member 10, where those inside corners are relatively adjacent to outer side walls 10c and 10d.

[0048] Because the material from which crack prevention member 10 is made is resilient and relatively thin at those separation regions, the material used to make crack prevention member 10, and/or the dimensions of crack prevention member 10, may be selected to enable separation along separation regions 10h and/or 10i such as by flexing by hand, or by cutting with a manual tool, such as a utility knife or a hand saw including but not limited to a hack saw or drywall saw, or with a power tool including but not limited to a jigsaw, reciprocating saw, or table saw. Separation of crack prevention member 10 along only separation region 10h will result in first crack prevention member portion 10j becoming a separate piece, with second crack prevention member portion 10k, and third crack prevention member portion 10l remaining joined. Further separation of crack prevention member 10 along separation region 10i will result in three separate pieces; first crack prevention member portion 10j, second crack prevention member portion 10k, and third crack prevention member portion 10l.

[0049] The ability to separate the present crack prevention member into portions allows those portions to be used as such, or combined in various configurations. FIG. 7B shows two such portions, first crack prevention member portion 10j and second crack prevention member portion 10k, such as might result from separating the crack prevention member of FIG. 7A along separation regions 10h and 10i to form three separate triangular portions, and using two of those portions to form a crack prevention member that could, for example, be used with a wooden support column that is positioned in a corner of a building structure. Alternatively, FIG. 7B also shows what could result from separating the crack prevention member in FIG. 7A along separation region 10h only, and using the larger resulting portion, having the shape of two joined triangles.

[0050] Similarly, FIG. 7C shows a configuration of the present crack prevention member having four triangular portions 10j-10m, which can be used in connection with a wooden support column that does not have any side adjacent a wall of the building structure. This configuration may be created by (a) combining two portions each consisting of two joined triangular crack prevention member portions; (b) combining four, individual triangular portions; or (c) combining a single, separated triangular crack prevention member portion with an unseparated crack prevention member (as shown for example in FIG. 4A).

[0051] Therefore, if a given crack prevention member is separated into portions during construction as herein described and not all of those portions are used with a particular wooden support column, those portions that are not used may still be used elsewhere in construction, whether by themselves, in combination with other separated portions, or with an unseparated crack prevention member. As another example, one triangular portion may be separated from a crack prevention member with the remaining portion consisting of two joined triangular portions used with a wooden support column that is positioned in a corner, such as shown in FIG. 5B at upper right, and in FIG. 8. The remaining, single triangular component may be combined with an unseparated crack prevention member for use with a wooden support column that is not adjacent a wall of the building structure, such as shown for example in FIGS. 6 and 7C. Many such combinations are possible and will be readily apparent to one of ordinary skill in the art.

[0052] It will further be appreciated that while FIGS. 7A-7C illustrate crack prevention members in which the components that may be created by separation along separation regions 10h and 10i are triangular, other shapes are possible depending on the shape of the crack prevention member to which separation is applied, including but not limited to semi-circular.

[0053] FIG. 8 shows an embodiment of the present system in which crack prevention member 10 may be formed as discussed in relation to FIG. 7B. Wooden support column 18 is positioned in a corner of a wall of the building structure, with base 18a positioned within cut-out portion 15 of crack prevention member 10. Base 18a is supported by ground surface 16; a concrete floor has not yet been poured. Crack prevention member 10 is attached to outer skirt board 21 by one or more fastening members 24.

[0054] FIG. 9 shows an embodiment of the present system in which wooden support column 18 is positioned with only one face adjacent a wall of the building structure, with base 18a within cut-out portion 15. Concrete floor 12 has been poured only up to the level of first surface 10a of crack prevention member 10, without being allowed to flow onto first surface 10a and contact wooden support column 18. Crack prevention member 10 is attached to outer skirt board 21 through fastening means which, because they are below the surface of concrete floor 12, are not visible. As may be seen, neither the concrete of concrete floor 12 nor any other structural concrete contacts wooden support column 18.

[0055] The present system and method allows saw cuts in a concrete floor to extend to a point adjacent a corner or vertice of the present crack prevention member, as shown for example in FIGS. 5A, 5B, and 6. With particular reference to FIG. 10, it will be appreciated that in the absence of crack prevention member 10, such that concrete floor 12 extended to the base of wooden support column 18, the housing of a concrete saw or saw cart would contact wooden support column 10 before the edge of the cut reached the edge of the concrete. With crack prevention member 10 in place, however, the tip 28a of saw cut 28 may extend to a point adjacent the corner of crack prevention member 10.

[0056] While the present system and method have been described with reference to particular embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the intended scope. Therefore, it is intended that the scope not be limited to the particular embodiments disclosed herein, but rather will include all embodiments falling within the scope and spirit of the application, including the appended claims.