US20080028699A1 - Foot tread and method of assembling same - Google Patents

Abstract

A stair tread comprising a tread center manufactured from a plurality of elongated wood members. Each elongated wood member receives a lamination of higher quality wood which is glued to each elongated wood member. The elongated wood members are then edge glued to form a tread body. A nose member is attached to leading edge of the tread body and is manufactured from a single unbroken piece of high-quality wood. Additionally, a heel member manufactured from a single unbroken piece of higher quality wood is attached to the rear edge of the tread body. A side member manufactured from higher quality wood may be positioned adjacent each edge of the tread body as well.

Description

BACKGROUND OF THE INVENTION
• 1. Technical Field
• This invention relates generally to stair treads. More particularly, the invention relates to engineered stair treads. Specifically, the invention relates to a stair tread which includes an inner core that is made from a plurality of horizontally oriented layers beneath an upper lamella and a solid wood portion adjacent the front and rear edge.
• 2. Background Information
• Stair treads have been made from solid pieces of wood for many years. However, with the rising cost of wood, it has become customary to manufacture stair treads with an inner core of an inexpensive or inferior wood and to cover this core with a veneer of a more expensive and superior wood. Additionally, a solid front nosing is ordinarily provided on the stair tread as this portion of the stair tread is ordinarily exposed during normal use. This gives the stair tread the appearance of being manufactured entirely of the superior wood, but reduces the production cost of the stair tread and also offers a more stable tread against movement. This type of disclosure can be found in Belgrade U.S. Pat. No. 5,985,398 which provides a stair tread having an aesthetic appearance of a solid hard wood stair tread and presents a core layer made of lamellas of lower quality material glued laterally adjacent to each other. A nosing is provided along the forward portion of the stair tread. Weber, et al., U.S. Pat. No. 6,860,071 also provides for a stair tread having predetermined dimension which includes a bottom and top that are at least substantially parallel whereby a plurality of bottom lamellas are glued together along with a solid wood front nosing. Additionally, a top surface is provided which is thinner and made of a higher quality lamella.
• While these devices are sufficient for the purpose for which they are intended, they include a number of drawbacks. Most notably, the lower quality wood can be seen from the rear portion of the stair tread. As homes with more open designs are developed, open stair cases whereby a rear portion of the stair tread is visible are becoming more common. Therefore, the need exists for a stair tread which has a higher quality wood adjacent the rear portion thereof. Further, while it is known to manufacture stair treads having a lower quality lamella covered by an upper quality thinner lamella in order to assure a more stable wood stair tread, the treads would be even more stable if assembled such that the upper lamella and lower lamella along longitudinal lengths of wood were first laminated and then edge glued one to another along the thickness of the tread. In this manner, a more stable stair tread will be provided.
• There is therefore a need in the art for improved engineered stair tread that will not warp and bow over time and that is aesthetically appealing from the top, front and rear portions of the tread and which is stable and strong enough to support the cyclic use of the stair tread.
BRIEF SUMMARY OF THE INVENTION
• The present invention provides a stair tread comprising a tread center having a top surface made from a lower quality wood having a leading edge and a rear edge; an elongated heel member made from a high-quality wood attached to the rear edge of the tread center; an elongated wooden nose member made from a higher quality wood attached to the leading edge of the tread center; and a lamination of higher quality wood extending over the top surface of the tread center.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
• The preferred embodiments of the invention, illustrative of the best mode in which applicant has contemplated applying the principles, are set forth in the following description, are shown in the drawings and are particularly and distinctively pointed out and set forth in the appended claims.
• FIG. 1 is a perspective view of the stair tread in accordance with the present invention;
• FIG. 2 is a side elevational view of the stair tread shown inFIG. 1;
• FIG. 3 is a sectional view taken along Line5-5,FIG. 1;
• FIG. 4 is an exploded assembly view of the stair tread shown inFIG. 1;
• FIG. 5 is a partially exploded assembly view of the stair tread shown inFIG. 1;
• FIG. 6 is a cutaway view of a second embodiment of the stair tread of the present invention;
• FIG. 7A is a sectional view taken along Line7A-7A,FIG. 6;
• FIG. 7B is an alternative embodiment of a method of joining adjacent pieces of the stair tread shown inFIG. 6;
• FIG. 7C is an alternative embodiment of a method of joining adjacent pieces of the stair tread shown inFIG. 6;
• FIG. 7D is an alternative embodiment of a method of joining adjacent pieces of the stair tread shown inFIG. 6;
• FIG. 7E is an alternative embodiment of a method of joining adjacent pieces of the stair tread shown inFIG. 6;
• FIG. 8 is an exploded assembly view of a third embodiment of the stair tread of the present invention;
• FIG. 9 is a partially assembled view of the stair tread of the present invention;
• FIG. 10 is a side elevational view of the third embodiment of the stair tread of the present invention; and
• FIG. 11 is a sectional view of the third embodiment of the stair tread of the present invention.
• Similar numbers refer to similar parts throughout the drawings.
DETAILED DESCRIPTION OF THE INVENTION
• The preferred embodiment of the wooded stair tread in accordance with the present invention illustrated inFIGS. 1-5 is generally identified by thereference numeral1. In the embodiment ofFIGS. 1-5, thewooden stair tread1 comprises three elongatedwooden members10,12 and14 to define atread center16 having a leadingedge18 and arear edge20 parallel to and spaced apart from leadingedge18.Tread center16 is also bounded by a pair ofside edges22.
• In accordance with one of the specific features of the invention,tread center16 is bounded on its leading edge by a solidwood nose member24 having a roundedforward edge25 to reduce chipping and to increase the aesthetic appeal ofstair tread1 and extending the entire length thereof. Additionally, a solidwood heel member26 is mounted alongrear edge20 oftread center16. Optionally,solid wood sides28 may be mounted alongside edges22 oftread center16 and may be butt-jointed against the edge ofheel member26.Side members28 andnose member24 may be attached by any convenient attachment means and are shown as amiter joint30 in the attached drawings. As can be seen fromFIG. 1,tread center16 is surrounded on all four sides bysolid wood members24,26 and28.
• Referring specifically toFIGS. 2 and 3, it can be seen thatelongated wood members10,12 and14 oftread center16 have a first thickness. Each of these members is covered by anupper lamination32. In accordance with one of the primary features of the invention, elongatedwooden members10,12 and14 are made of an inferior quality wood which would maketread center16 relatively inexpensive to manufacture and define the majority of the thickness ofstair tread1.Upper lamination32 is made of a higher quality wood, such as red oak, maple, mahogany, white oak or cherry, and is relatively thin in comparison to elongatedwooden members10,12 and14 to provide a nice appearance totread center16.Lamination32 has a thickness that is less than 30% and more preferably 20% of the first thickness of elongatedwooden members10,12 and14, elongatedwooden members10,12 and14 oftread center16 andlamination32 define atread body33. In further accordance with one of the primary features of the invention,nose member24 andheel member26 are manufactured from high quality wood such as that which is used to manufactureupper lamination32.Nose member24 andheel member26 have a height equal to the combined heights of elongatedwooden members10,12 and14 as well aslaminations32. In this manner, when laminations32 are installed on elongatedwooden members10,12 and14 andheel members26 andnose member24 are installed on the leadingedge18 andrear edge20 oftread center16, atop surface34, which is substantially level, is provided. Additionally,side members28 would also be of a height equal tonose member24 andheel member26 to provide a continuoustop surface34 whenside members28 are installed. Elongatedwooden members10,12 and14 are attached to laminations32 and tonose member24,heel member26 andside members28 by way of a thickness ofglue36. The thickness ofglue joints36 are exaggerated inFIG. 3 and have a de minimis thickness when manufactured. As can be seen, elongatedwooden members10,12 and14,nose member24 andheel member26 are all attached with a traditional butt joint, as shown inFIGS. 2 and 3. However, a variety of other joints may be used to add strength to thecomposite stair tread1.
• Referring toFIGS. 6 and 7A, ahole40 may be drilled into adjacent members ofstair tread1 and adowel pin42 may be positioned within the hole to provide added strength as well as to assist when aligning the various members ofstair tread1. Still further and referring specifically toFIG. 7B, a lap joint may be provided wherein arabbit44 is cut into the edge of each of therespective members10,12,14,24 and26.Rabbit44 of respective boards would be cut on opposite surfaces in order to allow them to matingly engage, as shown inFIG. 7B.
• Referring toFIGS. 7C and 7D, a zigzag configuration may be provided in order to create more glue surface and to assist when aligningrespective members10,12,14,24 and26. A final version is to provide a tongue and groove arrangement, such as that shown inFIG. 7E.
• In accordance with another element of the present invention and referring specifically toFIGS. 4 and 5, the method of manufacture is described. Elongatedwooden members10,12 and14 are first laminated by way ofglue36 each to alamination32 having a width similar to the associated elongated wooden member as is indicated by arrow A. Once each elongatedwooden member10,12 and14 has an associatedlamination32 attached thereto, they are laminated to each other by way ofglue36 and toheel member26 andnose member24, as is indicated by arrow B. In this manner, laminations A give the appearance that they each represent an individual solid piece of wood that would comprise both the elongated wooden member associated with eachlamination32. The glue lines betweenlaminations32 give the appearance that the wood is solid just asheel member26 andnose member24 are solid. In furniture manufacture as well as in fine carpentry, generally large expansives of wood are not utilized for things such as stair tread and the glue lines would give the appearance that it was a crafted member, rather than a manufactured member using lowerquality tread center16 surrounded byhigher quality laminations32,nose member24 andheel member26.
• It can be seen that by providing asolid heel member26 as well as asolid nose member24, the stair tread will remain extremely stable given that it has solid wood adjacent both longitudinal edge surfaces oftread center16. Ifstair tread1 is utilized on an open staircase, having asolid heel member26 will provide a more aesthetically appealing stair tread when viewed from the bottom or rear of the open staircase.
• Referring next to the second embodiment of the invention shown specifically inFIGS. 8-11 and referenced by the numeral50, it can be seen thatstair tread50 is similar tostair tread1 in every respect, except that abottom lamination52 is provided by way ofglue joints36 to elongatedwooden members10,12 and14. Referring to the method of manufacture and specifically toFIG. 8, it can be seen that each elongated member ofstair tread50 is reduced in thickness with respect to the elongated members shown with respect to stair tread to provide sufficient room to acceptbottom laminations52.Top laminations32 andbottom laminations52 are each applied to an individual elongatedwooden member10,12 and14 by way ofglue36. Referring toFIG. 9, each assembled laminated elongatedwooden member10 is glued one to another and a solidwood heel section26 andnose section24 are applied to the edge portions oftread center16. In this manner, a stair tread that gives the appearance of high quality wood from both the top and bottom may be manufactured for use on open stairways and the like.
• While the preferred embodiment of the stair tread of the present invention is being disclosed as made entirely from wood from the same species, with the outer region comprising higher grades of that wood and the inner core comprising lower grades of the same species, it will be understood by those skilled in the art that the entire core may alternatively be manufactured from different, less expensive, lower grade lumbers, including manufactured wood products, such as chipped board or particle board or medium density fiber board. Additionally, the inner core may be manufactured from less expensive natural wood varieties, such as pine or poplar.
• In the foregoing description, certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed.
• Moreover, the description and illustration of the invention is an example and the invention is not limited to the exact details shown or described.

Claims (17)

1. A stair tread comprising;

a tread center having a top surface made from a lower quality wood having a leading edge and a rear edge;

an elongated heel member made from a high-quality wood attached to the rear edge of the tread center;

an elongated wooden nose member made from a higher quality wood attached to the leading edge of the tread center; and

a lamination of higher quality wood extending over the top surface of the tread center.

2. The stair tread ofclaim 1 wherein the nose member and heel member each have an edge and an upper surface; and in which the lamination abuts the edge adjacent the upper surface.

3. The stair tread ofclaim 2 in which the tread center has a first thickness and the lamination has a second thickness and in which the second thickness is less than 30% of the first thickness.

4. The tread center ofclaim 3 in which the nose member and the heel member have a third thickness and in which the third thickness equals the sum of the first and second thicknesses.

5. The stair tread ofclaim 2 in which the nose member, heel member and tread member define a pair of edges and in which a solid wood side is attached to at least one of the edges.

6. The stair tread ofclaim 5 in which a solid wood side is attached to both of the side edges.

7. The stair tread ofclaim 2 in which the lamination, heel member and nose member are manufactured of the same material.

8. The stair tread ofclaim 2 in which the heel member is a solid unbroken piece of higher quality wood.

9. The stair tread ofclaim 8 in which the tread center further comprises a plurality of elongated wood members, each having a width and an edge and in which the edges adjacent elongated wood members are attached.

10. The stair tread ofclaim 9 in which each lamination has a width equal to the width of the associated elongated wooden member of the tread center.

11. The stair tread ofclaim 10 in which the tread center is made from at least three elongated wooden members.

12. The stair tread ofclaim 11 in which the heel member has a width equal to at least 40% of the width of the smallest width elongated wooden member.

13. The stair tread ofclaim 12 in which each elongated wooden member has an equal width and in which the heel member has a width equal to said equal width.

14. The stair tread as defined inclaim 11 in which the elongated wood members and laminations are joined to form a tread body and in which the nose member and heel members are joined to the tread body.

15. The stair tread ofclaim 2 in which the elongated wooden members are attached to one another and in which each of the nose member and heel member are attached to one another by a joint consisting of one from the group of butt joint, lap joint, dowel pin joint, zigzag joint and tongue and groove joint.

16. The stair tread ofclaim 15 in which all joint in the stair tread are the same.

17. The stair tread ofclaim 2 further comprising a bottom lamination of higher quality wood and in which the stair tread has a bottom surface and in which the bottom lamination of higher quality wood is secured to the bottom surface of the stair tread.

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