Hidden Interconnection Arrangement of Fence or Railing and Assembling Method Thereof

Abstract

An assembling method of a hidden interconnection arrangement of fence or railing is provided, wherein a downward force applied to a top wall of a lateral beam is able to press a bottom guider edge of a lower engaging arm downwards against a top edge of an engaging rail that generates a reaction force to enlarge a bottom opening of the lateral beam to allow the engaging rail to be engaged in an engaging recess and locked between an upper engaging arm and the lower engaging arm of the lateral beam while fasteners that fastened the engaging rails to a plurality of upright posts are hidden and concealed by the lateral beams and the pressing walls of the lateral beams press against flat surfaces of the upright posts respectively.

Claims

1-10. (canceled)

11. A railing device, comprising: a plurality of upright posts each having a flat surface, a fastening surface and two or more fastening holes spacedly formed in an upper position and a lower position of said fastening surface; two or more lateral beams, each having a top wall, a pressing wall and an engaging wall, wherein said top wall of each of said lateral beams has a plurality of connection openings formed at spaced intervals, said pressing wall and said engaging wall being extended from two longitudinal sides of said top wall to define a receiving chamber therebetween and a bottom opening having a width smaller than a width of said top wall; and a hidden interconnection arrangement, comprising: two or more, elongated, engaging rails each having a flat side, a concave side opposing said flat side, and a plurality of position holes formed and extended from said concave side to said flat side at spaced intervals; a plurality of fasteners configured to pass through said position holes of said engaging rails and fasten to said fastening holes of said upright posts, such that said two or more engaging rails are fastened laterally across said lateral beams so as to fasten said plurality of said upright posts in parallel upright manner; and a pair of upper engaging arm and lower engaging arm integrally protruded from an inner surface of said engaging wall of each of said lateral beams, defining an engaging recess between said upper engaging arm and said lower engaging arm, wherein a height of each of said upper engaging arm and said lower engaging arm is equal to or larger than a thickness of each of said engaging rails, such that a downward force applied to said top wall of one of said two or more lateral beams is able to press said lower engaging arm downwards to allow said engaging rail to be engaged in said engaging recess and locked between said upper engaging arm and said lower engaging arm of said lateral beam while said fasteners that fastened said engaging rails to said upright posts are hidden and concealed by said lateral beams and said pressing walls of said lateral beams press against said flat surfaces of said upright posts respectively.

12. The railing device, as recited in claim 11, further comprising a top engaging rail and a top lateral beam, wherein a plurality of top position holes, wherein each of said plurality of upright posts has a top fastening hole and said top engaging rail is fastened to top ends of said plurality of said upright posts by passing through said fasteners said top position holes of said top engaging rail and fastening said fasteners to said top fastening holes of said upright posts, wherein a pair of top upper engaging arm and top lower engaging arm integrally from a top inner surface of a top engaging wall of said top lateral beam defines a top engaging recess between said top upper engaging arm and said top lower engaging arm to engage said top engaging rail therein so as to mount said top lateral beam to said top ends of said plurality of said upright posts.

13. The railing device, as recited in claim 11, further comprising at least one tubular end post assembled thereto form a fence, wherein said end post has two or more end holes spacedly formed in an inner wall thereof, each of said two or more end holes having a size and shape corresponding to a cross sectional size and shape of each of said two or more lateral beams, such that end portions of said two or more lateral beams are able to fittingly insert through said end holes respectively.

14. The railing device, as recited in claim 13, wherein said hidden interconnection arrangement further comprises two or more resilient lockers and each of said end portions of said two or more lateral beams has a pair of locker holes formed in two opposing sides thereof, wherein each of said resilient lockers comprises a V shape resilient member and two locker stubs outwardly extended from two ends of said resilient member respectively, wherein said two or more resilient lockers are configured to be inserted into said end portions of said two or more lateral beams respectively, such that said end portion transversely inserted into said end post through said end hole until said pair of said locker holes being passed through said end hole and positioned in said end post is able to be locked in position by extending said two locker stubs out through said pair of locker holes of said lateral beam corresponding so as to lock said end portion of said lateral beam with said end post.

15. The railing device, as recited in claim 12, further comprising at least one tubular end post assembled thereto form a fence, wherein said end post has two or more end holes spacedly formed in an inner wall thereof, each of said two or more end holes having a size and shape corresponding to a cross sectional size and shape of each of said two or more lateral beams and said top lateral beam, such that end portions of said two or more lateral beams and said top lateral beam are able to fittingly insert through said end holes respectively.

16. The railing device, as recited in claim 15, wherein said hidden interconnection arrangement further comprises two or more resilient lockers and each of said end portions of said two or more lateral beams and said top lateral beam has a pair of locker holes formed in two opposing sides thereof, wherein each of said resilient lockers comprises a V shape resilient member and two locker stubs outwardly extended from two ends of said resilient member respectively, wherein said two or more resilient lockers are configured to be inserted into said end portions of said two or more lateral beams and said top lateral beam respectively, such that said end portion transversely inserted into said end post through said end hole until said pair of said locker holes being passed through said end hole and positioned in said end post is able to be locked in position by extending said two locker stubs out through said pair of locker holes of each of said two or more lateral beams and said top lateral beam.

17. The railing device, as recited in claim 13, wherein each of said end portions of said two or more lateral beams has a pair of locker holes formed in two opposing sides thereof and an indented corner recess is formed at an end of said end portion of each of said two or more lateral beams to define a stopper edge adapted to be pressed against a wall surface adjacent said end hole of said end post after said end portion is inserted into said end post through said end hole while said pair of locker holes of each of said two or more lateral beams being passed through said end hole and positioned in said end post.

18. The railing device, as recited in claim 14, wherein an indented corner recess is formed at an end of said end portion of each of said two or more lateral beams to define a stopper edge adapted to be pressed against a wall surface adjacent said end hole of said end post after said end portion is inserted into said end post through said end hole while said pair of locker holes of each of said two or more lateral beams being passed through said end hole and positioned in said end post.

19. The railing device, as recited in claim 15, wherein each of said end portions of said two or more lateral beams has a pair of locker holes formed in two opposing sides thereof and an indented corner recess is formed at an end of said end portion of each of said two or more lateral beams and said top lateral beam to define a stopper edge adapted to be pressed against a wall surface adjacent said end hole of said end post after said end portion is inserted into said end post through said end hole while said pair of locker holes of each of said two or more lateral beam and said top lateral beam being passed through said end hole and positioned in said end post.

20. The railing device, as recited in claim 16, wherein an indented corner recess is formed at an end of said end portion of each of said two or more lateral beams and said top lateral beam to define a stopper edge adapted to be pressed against a wall surface adjacent said end hole of said end post after said end portion is inserted into said end post through said end hole while said pair of locker holes of each of said two or more lateral beam and said top lateral beam being passed through said end hole and positioned in said end post.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] FIG. 1 is a front view of a conventional metal fence.

[0039] FIG. 2 is a cross-sectional view of line 2-2 in FIG. 1.

[0040] FIG. 2A is a partial enlarged view of the part marked (A) in FIG. 2.

[0041] FIG. 2B is a partial enlarged view of the part marked (B) in FIG. 2.

[0042] FIG. 2C is a partial enlarged view of the part marked (D) in FIG. 2.

[0043] FIG. 3 is a perspective view of a fence with hidden interconnection arrangement according to a preferred embodiment of the present invention.

[0044] FIG. 4 is an end perspective view of a lateral beam of the fence with hidden interconnection arrangement according to the above preferred embodiment of the present invention.

[0045] FIG. 5 is an end view of a lateral beam and an upright post of the fence with hidden interconnection arrangement according to the above preferred embodiment of the present invention.

[0046] FIG. 6A is a front view illustrating the upright posts of the fence with hidden interconnection arrangement at spaced intervals according to the above preferred embodiment of the present invention.

[0047] FIG. 6B is a front view illustrating the upright posts interconnected by an engaging rail of the fence with hidden interconnection arrangement according to the above preferred embodiment of the present invention.

[0048] FIG. 7 is a perspective view illustrating the upright posts interconnected by the engaging rail of the fence with hidden interconnection arrangement according to the above preferred embodiment of the present invention.

[0049] FIG. 8 is a top view illustrating the interconnection of the upright post, the lateral beam and the engaging rail of the fence with hidden interconnection arrangement according to the above preferred embodiment of the present invention.

[0050] FIG. 9 is a bottom perspective view of the fence with hidden interconnection arrangement according to the above preferred embodiment of the present invention.

[0051] FIG. 10 is a partial exploded perspective of the fence with hidden interconnection arrangement according to the above preferred embodiment of the present invention.

[0052] FIG. 11 is a partial perspective view of an end portion of the lateral beam of the fence with hidden interconnection arrangement according to the above preferred embodiment of the present invention.

[0053] FIG. 12 is a partial perspective view illustrating the interconnection of the lateral beams and the end post of the fence with hidden interconnection arrangement according to the above preferred embodiment of the present invention.

[0054] FIG. 13 is a perspective view of a locker of the fence with hidden interconnection arrangement according to the above preferred embodiment of the present invention.

[0055] FIG. 14 is a partial perspective view illustrating the end portion of the lateral beam interlocked with the end post with the locker of the fence with hidden interconnection arrangement according to the above preferred embodiment of the present invention.

[0056] FIG. 15A to FIG. 15F are schematic views illustrating an assembling method of a hidden interconnection arrangement of fence or railing according to the above preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0057] The following description is disclosed to enable any person skilled in the art to make and use the present invention. Preferred embodiments are provided in the following description only as examples and modifications will be apparent to those skilled in the art. The general principles defined in the following description would be applied to other embodiments, alternatives, modifications, equivalents, and applications without departing from the spirit and scope of the present invention.

[0058] The present invention discloses a hidden interconnection arrangement 30 of fence or railing and assembling method thereof. Referring to FIG. 3 to FIG. 14, a fence 1 comprises at least an end post 10 and a railing device 20, wherein the railing device 20 comprises a plurality of upright posts 21 and two or more lateral beams 22 interconnected the plurality of the upright posts 21 at spaced interval by means of a hidden interconnection arrangement 30 (as shown in FIG. 5). The number of the upright posts 21 determines a length of the fence 1, wherein the pair of sectional broken lines as shown in FIG. 1 demonstrates a predetermined length of the lateral beams 22 and numbers of the upright posts 21 for illustration purpose in the drawing.

[0059] Referring to FIG. 5 to FIG. 8, each of the plurality of the upright posts 21 is an elongated tubular member made of rigid material such as metal, which has a flat surface 211, a fastening surface 212 and two or more fastening holes 213 spacedly formed in at least an upper position and a lower position of the fastening surface 212.

[0060] Referring to FIG. 4 and FIG. 5, each of the two or more lateral beams 22 has a top wall 221, a pressing wall 222 and an engaging wall 223, wherein the pressing wall 222 and the engaging wall 223, defining a receiving chamber 224 between the pressing wall 222 and the engaging wall 223 and a bottom opening 225. The engaging wall 223, which is perpendicularly extended from one longitudinal side of the top wall 221, has a lower engaging arm 2231 and an upper engaging arm 2232 and an reinforcing rib 2233, wherein the two engaging arms 2231, 2232 are integrally and parallelly protruded from a lower portion of the engaging wall 223 inwardly in the receiving chamber 224 to define an engagement recess 2234 between the two engaging arms 2231, 2232, and the reinforcing rib 2233 is integrally protruded from an upper portion of the engaging wall 223 to provide a reinforcing support to engaging wall 223. The pressing wall 222 is a resilient wall slantly extended from another longitudinal side of the top wall 221 such that a width of the bottom opening 225 is slightly narrower than a width of the top wall 221 to provide an elastic effect, wherein a pair of contact bulges 2221, 2222 formed on an inner surface of the pressing wall 222 configured for reducing a contact area of the pressing wall 222 and the upright posts 21 and applying a pressing force against the upright posts 21 positioned in the receiving chamber 224. It is worth mentioning that a height of each of the contact bulges 2221, 2222 is preferred to be much smaller than a thickness of the pressing wall 222 for simply reducing the contact area of the pressing wall 222 and a height of each of the engaging arms 2231, 2232 is preferred to be larger than a thickness of the engaging wall 223 for providing an engagement ability.

[0061] One of the each of the two or more lateral beams 22 is a top lateral beam 22, as shown in FIG. 4, and one or more of the lateral beams 22 are further configured as interconnecting lateral beams 22 each of which top wall 221 has a plurality of connection openings 2211 formed at spaced intervals, as shown in FIG. 5 to FIG. 6B. The size and shape each of the connection openings 2211 are configured to allow one corresponding upright post 21 to penetrate through, wherein each of the connection openings 2211 has a size equal to or larger than a cross sectional size of each of the upright posts 21.

[0062] According to the preferred embodiment, as shown in FIG. 3, three lateral beams 22, including two interconnecting lateral beams 22 interconnecting crossingly with upper portions and lower portions of the plurality of the upright posts 21 and one top beam 22 being mounted on top ends of the plurality of the upright posts 21.

[0063] Referring to FIG. 5, to FIG. 8, the hidden interconnection arrangement 30 comprises the engaging arms 2231, 2232 protruded on the inner surface of the engaging wall 223 of each of the lateral beams 22 as described above and two or more, elongated, engaging rails 31, made of rigid metal, each having a flat side 311, a concave side opposing the flat side 312, and a plurality of position holes 313 formed and extended from the concave side 312 to the flat side 311 at spaced intervals. According to the preferred embodiment, three lateral beams 22 are embodiment and, correspondingly, three engaging rails 31 are configured while each of the upright posts has three fastening holes 213 formed at a top position, an upper position and a lower position respectively, such that the three engaging rails 31 can be fastened across the upright posts 21 in a parallel manner so as to configured a rigid railing device. In order words, the rigid engaging rails 31 substantially support the upright posts 21 in upright position at spaced intervals.

[0064] The hidden interconnection arrangement 30 further comprises a plurality of fasteners 32 configured to pass through the position holes 313 of the engaging rails 31 and fasten to the fastening holes 213 of the upright posts 21, such that the two or more engaging rails 31 are fastened laterally across the lateral beams 22 so as to fasten the upright posts 21 in parallel upright manner. According to the preferred embodiment, the fasteners 32 are embodied as screws and the fastening holes 213 of the upright posts 21 are embodied as screw holes correspondingly. In addition, the position holes 313 of the engaging rail 31 can be through holes or screw holes corresponding to the screwing fasteners 32.

[0065] The lower engaging arm 2231 and upper engaging arm 2232 are integrally protruded from the inner surface of the engaging wall 223 of each of the lateral beams 22 and preferred to each having a height larger than a thickness of the engaging rail 31, wherein a width of the engaging recess 2234 is equal to or slightly wider than a width of each of the engaging rails 31, such that the engaging recess 2234 defined between the lower and upper engaging arms 2231, 2232 is able to be fittingly received the engaging rail 31 therein and locked in position.

[0066] According to the preferred embodiment, as shown in FIG. 4, a curved bottom guider edge 22311 is formed along the lower engaging arm 2231, such that a downward force applied to the top wall of one of the lateral beams 22 is able to press the bottom guider edge 2311 of the lower engaging arm 2231 downwards against a top edge 310 of one of the engaging rails 31, as shown in FIG. 7, that generates a reaction force to enlarge the bottom opening 225 of the lateral beam 22 to allow the engaging rail 31 to be engaged in the engaging recess 2234 and locked between the upper engaging arm 2232 and the lower engaging arm 2231 of the lateral beam 22 while the fasteners 32 that fastened the engaging rail 31 to the upright posts 21 are hidden and concealed by the lateral beam 22 and the pressing wall 222 of the lateral beam 21 presses against the flat surfaces 211 of the upright posts 21, as shown in FIG. 5.

[0067] In other words, the lateral beams 22 are utilized to hide and cover the engaging rails 31 which are the elements for supporting and fastening the upright posts 21 in upright and parallel position to form a railing system. Therefore, the lateral beams 22 can be made thinner that not only reduces the cost of material but also provides a resilient ability rendering the slightly slanting inwards pressing wall 222 to form a resilient element adapted to press against the upright posts 21, such that the lateral beams 22 may also strengthen and support the engaging rails 31 respectively.

[0068] Since the upright posts 21, the lateral beams 22 and the engaging rails 31 of the railing device 20 can be packed before assembly so as to minimize the packaging size that substantially reduces the transportation size and cost. At the jobsite, the user may assemble the railing device 20 by the following steps: [0069] (a) aligning the plurality of the upright posts 21 spacedly in parallel manner; [0070] (b) mounting the interconnecting lateral beams 22 crossingly with the upright posts 21 by inserting the upright posts 21 through the plurality of the connection openings 2211 formed at spaced intervals in the top wall 221 of each of the interconnecting lateral beams 22 respectively, wherein each of the interconnecting lateral beams 22 has the pressing wall 222 and the engaging wall 223 extended from two longitudinal sides of the top wall 221 to define the bottom opening 225 therebetween while the pressing wall 222 forms a resilient arm to press against the upright posts 21; [0071] (c) fastening the engaging rails 31 across the plurality of the upright posts 21 laterally by inserting the plurality of the fasteners 32 through the plurality of the position holes 313 formed in the engaging rails 31 at spaced intervals and screwing the fasteners 32 to the fastening holes 213 spacedly formed in the upper position and the lower position of the fastening surface 212 of each of the plurality of the upright posts 21 respectively, wherein the flat sides 311 of the engaging rails 31 are flatly placed on the engaging surfaces 212 of the upright posts 21; and [0072] (d) engaging the engaging rails 31 fastened to the upper positions and the lower positions of the upright posts 21 in the engaging recesses 2234 formed in the inner surfaces of the engaging walls 223 of the two interconnecting lateral beams 22 respectively by pressing the interconnecting lateral beams 22 downwardly toward bottom ends of the upright posts 21 until the upright posts 21 are interconnected with the engaging rails 31 so as to mount the interconnecting lateral beams 22 across the upright posts 21 laterally, as shown in FIG. 9.

[0073] It is appreciated that, through the step (b), the upright posts 21 are spacedly arranged in position by means of the interconnecting lateral beams 22 that significantly facilitates the subsequent step (c) of fastening the engaging rails 31 to the upright posts 21 since the position holes 313 of the engaging rails 31 are easily to be aligned with the fastening holes 213 of the upright posts 21 respectively while the upright posts 21 are spacedly mounted by the interconnecting lateral beams 22.

[0074] When the railing device 20 includes a top lateral beam 22, the step (c) of the assembling method further comprises a step (c1) of fastening a top engaging rail 31 across top positions of the plurality of the upright posts 21 laterally by inserting the fasteners 32 through the position holes formed in the top engaging rail 31 at spaced intervals and fastening the fasteners 32 to the fastening holes 213 spacedly formed in a top position of the fastening surface 212 of each of the plurality of the upright posts 21 respectively, and the step (d) further comprises a step (d1) of engaging the top engaging rail 31 in the engaging recess 225 formed in an inner surface of the engaging wall 223 of the top lateral beam 22 respectively by sliding the top lateral beam 22 across the top engaging rail 31 while the top engaging rail 31 is engaged in an engaging recess 2234 formed in the inner surface of the engaging wall 223 of the top lateral beam 22 so as to mount the top lateral beam 22 across the top ends of the plurality of the upright posts 21 laterally.

[0075] According to the preferred embodiment, in the step (d), the downward pressing of the lateral beam 22 (either the top lateral beam 22 or the interconnecting lateral beam 22) against the corresponding engaging rail 31 enlarges the bottom opening 225 defined between two ends of the pressing wall 222 and engaging wall 223 to allow the corresponding engaging rail 31 to be positioned in the engaging recess 2234 of the lateral beam 22.

[0076] It is appreciated that the railing device 20 is configured to be able to assemble at the jobsite by the user through the step (a) to the step (d) and to preassemble by the manufacturers in a semi-automatic way by means of an assembling apparatus 40, as shown in FIG. 15A to FIG. 15F. Referring to FIG. 15A, the step (a) can be executed on a working platform 41 of the assembly apparatus 40 to align the plurality of the upright posts 21 spacedly in parallel manner, that facilitates the step (b) of mounting the interconnecting lateral beams 22 crossingly with the upright posts 21. Referring to FIG. 15B, the step (c) of screwing the fasteners 32 to fasten the engaging rails 31 to the upright posts 21 can be executed by screwdriver manually or by power tool.

[0077] After the step (c), referring to FIG. 15C to FIG. 15F, the step (d) can be executed by pushers 42 which are positioned adjacent to the lateral beams 22 and driven by a driving mechanism 43 powered by a hydraulic or electrical system 44. As shown in FIG. 15D, the step (d) is automatically executed by the hydraulic or electrical system 44 which actuates the driving mechanism 43 to move and push the pushers 42 to press against the lateral beams 22 towards the bottom ends of the upright posts 21 until the curved bottom guider edges 22311 formed along the lower engaging arms 2231 of the lateral beams 22 (as shown in FIG. 4) being guided by the engaging rails 31 to force the bottom openings 225 of the lateral beams 22 to be enlarged. As shown in FIG. 15E, the driving mechanism 43 continues to push the pushers 42 to press the lateral beams 22 towards the bottom ends of the upright posts 21 against the engaging rails 31 to push the engaging rails 31 to be engaged into the corresponding engaging recesses 2234 of the top lateral beam 22 and the interconnecting lateral beams 22 respectively until all the engaging rails 31 are completely engaged in the corresponding engaging recesses 2234 of the lateral beams 22 respectively, as shown in FIG. 15F.

[0078] According to the preferred embodiment, referring to FIG. 3 and FIGS. 10-14, the railing device 20 is configured to be assembled with a pair of end posts 10 to form the fence 1, wherein the end post 10 is embodied as a tubular post having two or more end holes 11 spacedly formed in an inner wall 101 of the end post 10, each having a size and shape corresponding to a cross sectional size and shape of each of the lateral beams 22. The hidden interconnection arrangement 30 further includes two end portions 226 of each of the lateral beams which are able to fittingly insert through the end holes 11 of the pair of the end posts 10 respectively. In addition, the hidden interconnection arrangement 30 further comprises two or more resilient lockers 34 and each of the end portions 226 of the lateral beams 22 has a pair of locker holes 2261 formed in two opposing sides thereof (as shown in FIG. 11). As shown in FIG. 11, each of the resilient lockers 34 comprises a V shape resilient member 341 and two locker stubs 342 outwardly extended from two ends of the resilient member 341 respectively. Each of the resilient lockers 34 is adapted to be inserted into the corresponding end portion 226 of the lateral beam 22, such that the end portion 226 transversely inserted into the end post 10 through the end hole 11 until the pair of the locker holes 2261 being passed through the end hole 11 and positioned in the end post 10 is able to be locked in position by extending the two locker stubs 342 out through the pair of locker holes 2261 of the corresponding lateral beam 22, as shown in FIG. 14, so as to lock the end portion 226 of the lateral beam 22 with the end post 10.

[0079] Alternatively, the end portion 226 of each of the lateral beams 22 can be inserted into the end post 10 through the corresponding end hole 11 until an end of the end portion 226 of the lateral beam 22 in contact with an inner surface of an outer wall of the end post 10.

[0080] According to the preferred embodiment, referring to FIG. 11, an indented corner recess 2262 is formed at an end of the end portion 226 of each of the lateral beams 22 to define a stopper edge 22621 adapted to be pressed against a wall surface 13 adjacent the end hole 11 of the end post 10, as shown in FIG. 12, after the end portion 226 is inserted into the end post 10 through the end hole 11, as shown in FIG. 14, while the pair of locker holes 2261 of the lateral beams 22 being passed through the end hole 11 and positioned in the end post 10.

[0081] Accordingly, to assemble the railing device 20 to form a fence, the assembling method further comprises steps of: [0082] (e) installing the V-shape resilient locker 34 in each the end portion 226 of each of the lateral beams 22; [0083] (f) fittingly inserting the end portions 226 of the lateral beams 22 through the end holes 11 spacedly formed on the inner wall 13 of the end post 10 until the pair of locker holes 2261 formed in two opposing sides of the end portion 226 of each of the lateral beams 22 being passed through the end hole 11 and positioned in the end post 10; and [0084] (g) locking the two locker stubs 342 protruded from two ends of the resilient member 341 of the locker 34 with the pair of locker holes by extending the two locker stubs through the two locker holes 2261 of the corresponding lateral beam 22 so as to lock the end portions 226 of the lateral beams 22 with the end post 10.

[0085] One skilled in the art will understand that the embodiment of the present invention as shown in the drawings and described above is exemplary only and not intended to be limiting.

[0086] It will thus be seen that the objects of the present invention have been fully and effectively accomplished. The embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.