Patent Application
20220090860
Not applicable.
Not applicable.
Not applicable.
Not applicable.
The present invention relates to kilns used for the drying and treatment of lumber and wood. More particularly, the present invention relates to kiln stickers as used for supporting the stacks of lumber or planks within the kiln.
When timber is harvested and hewn into lumber, it is considered green, that is, the lumber has not been conditioned and has a high internal moisture content. Green wood is often not desirable for use in many applications since the lumber will tend to shrink as it dries. This creates gaps or voids when used in construction of structures or objects. Additionally, as the lumber dries, it can warp, split or crack which can weaken or damage the structure or object created using the greenwood. Further, for some applications, the high moisture content of the wood can prevent its use as necessary or desired processes cannot be performed on the wood having a high internal moisture content.
To avoid these potentially negative drawbacks, the wood can be seasoned, allowing internal moisture of the wood to evaporate to a desired or sufficient level for use of the wood or lumber in a desired application. A typical method of seasoning is to leave the cut lumber outdoors, exposed to the elements, so as to allow the internal moisture content of the lumber to equalize with the local environment. Once equalized, the lumber will likely not change dimensionally when used in an application, i.e. the lumber will not warp or contract. To achieve this seasoning, the wood or lumber is left outside to season for an extended period ranging from months to years. As such, large areas needed to store the lumber as it seasons and a seller will have to wait during the seasoning time before selling the lumber.
To speed the process of seasoning, the lumber can be placed in a kiln to dry the lumber to the desired internal moisture content more rapidly. Lumber is placed within the kiln and heated to evaporate the internal moisture, seasoning the wood in a fraction of the time required for passively seasoning the wood or lumber outdoors. Kiln drying lumber can increase the cost of the final product since a larger economic investment is required to purchase and operate the necessary equipment. However, the reduced time to season the lumber and the control of the final moisture content of the lumber have economic benefits that justify the increased costs for the production of the final lumber product.
Traditionally, wood drying operations in wood drying kilns have used utilized wooden kiln stickers normally about three quarters of an inch thick and one and a half inches wide and as long as necessary. The species of wood used for application as stickers varies according to the type of mill and the geographic location. It is desirable to provide a straight kiln sticker and, to do so, knot-free straight green lumber having a large amount of sap would be desired. This type of lumber has the highest raw material cost. Such high-grade lumber is required to resist warpage, twist, compression and deflection of the wood stickers when subjected to the extreme weight and environmental conditions that exist in normal kiln drying operations.
Traditionally, most companies saw their own kiln stickers out of the existing lumber stock. This disrupts the normal production lines due to the changeover for the specific purpose of manufacturing kiln stickers. The kiln stickers in the dry kiln environment are exposed first to extremely wet conditions and then, as the lumber in the kiln is dried, to dry conditions. This combination of wet and dry conditions, plus the weight of the wood in the kiln, reduces the length of the wood kiln sticker and dries the sticker into a set condition. This can result in warpage and compression. When the wood kiln stickers are subjected to subsequent cycles, this warped condition is accentuated and creates jam-ups in the automatic equipment used for loading and unloading the kilns.
Reuse of wood kiln stickers also increases the compression set which occurs on the ends of each sticker and causes “domed” loads which reduce the size of the kiln charge that can be put into the kiln and can cause the kiln charge to overturn and tumble. Further, reuse of wood kiln stickers reduces the efficiency for air passage through the spaces in the lumber load resulting in an increased of drying time to achieve standard dry conditions. Repeated drying cycles using wood kiln stickers eventually degrades the stickers to the point where they must be disposed of, normally in a maximum of five to seven cycles.
The transverse extent of the top surface 16 is substantially less than the width of the sticker so that the area of contact between the lumber and the sticker is reduced when compared with conventional sticker designs. A practical width for the sticker across the bottom is one and a half inches. The width of the surface 16 for such a sticker will depend upon the strength of the sticker material, the hardness of the lumber, and the desire to avoid sticker shadow. It should also be wide enough to bear the load.
After the lumber or wood has been dried in the kiln, it will be necessary to move the lumber from the kiln to another location, such as for transport and storage. As such, a pair of conveyors are often employed. One set of the conveyors is employed so as to receive the planks of wood thereon. The second conveyor is utilized so as to receive the discarded kiln stickers (previously located between the courses of lumber). When the kiln stickers are discharged from the main conveyor, they can often become damaged or oriented in an improper direction. As such, as the kiln stickers are conveyed to another location, they must be inspected for quality and orientation. If the kiln stickers have become damaged or warped, it will be necessary to discard such kiln stickers and replace them. As such, a need has developed so as to provide kiln stickers which avoid the need for inspection, orientation and replacement.
In the past, various patents have issued with respect to kilns and kiln stickers used in such kilns. For example, U.S. Pat. No. 3,907,130, issued on Sep. 23, 1975 to D. Hutcheson, describes kiln stickers in the manner shown in
U.S. Patent Application Publication No. 2016/0290717, published on Oct. 6, 2016 to P. J. Wagner, describe stickers for drying and/or curing materials. The sticker has support members that extend radially outwardly from a central portion. An open-ended channel is configured to allow air flow therethrough. The open-ended channel is defined between each adjacent pair of support members. The central portion of at least a portion of the support members can have a X-shaped cross-sectional shape.
U.S. Patent Application Publication No. 2007/0101608, published on May 10, 2007 to G. Sundholm, discloses an apparatus for the treatment of wood and/or wood products. This apparatus has at least two treating elements between which moist wood or wood products are treated in conjunction with a drying or pressing process. The treating element at least partially consists of a plurality of tubular parts arranged adjacent to each other. A groove is provided between at least some of the adjacent tubular parts.
U.S. Pat. No. 6,134,803, issued Oct. 24, 2000 to Gilchrist et al., discloses a flexible wood sticker. This wood sticker is an elongated four-sided, solid high molecular weight polyethylene wood sticker which serves to separate the lowermost surfaces of uppermost laid-in planking from the uppermost surfaces of lowermost laid-in planking. The flexible wood sticker has four rounded edges marking the intersection of any two sides therein and also has a helically-inclined groove cut into the outer surfaces of all four sides thereof and extends uniformly from one end thereof to the other end thereof.
U.S. Pat. No. 5,813,137, issued on Sep. 29, 1998 to T. M. Townsend, discloses a sticker that is used in the lumber industry to separate pieces of lumber in a stack or in a bundle. The sticker has a plurality of grooves extending transverse to the length of the length of the sticker to permit air circulation within the grooves. There are plurality of ridges between the grooves that support the pieces of lumber.
U.S. Pat. No. 5,345,695, issued on Sep. 13, 1994 to A. B. Graham, discloses a method and apparatus for drying wood. Pieces of wood are stacked in an oven and have a space provided between horizontal layers of the wood so as to permit air flow between the pieces of wood. Channel-shaped, non-moisture absorbing strips of metal or plastic are used for the spacing. The air for drying the wood travels down the channel of the strips to help in the drying of the wood.
U.S. Pat. No. 3,900,957, issued on Aug. 26, 1975 to Denton et al., shows a method and system for drying wood. Courses of wood in the conventional drying kiln are separated by strong, dimensionally stable, re-usable kiln stickers made of paper-reinforced, thermosetting resin laminate having a thickness ranging from one-quarter inch to one inch. The laminate is made by saturating a resin-saturating paper with a thermosetting resin, such as phenol-formaldehyde resin or lignin-phenol-formaldehyde resin.
It is another object of the present invention to provide a kiln sticker that enhances airflow between courses of wood and lumber.
It is another object of the present invention to provide a kiln sticker that is self-righting.
It is another object of the present invention to provide a kiln sticker that is reusable.
It is a further object of the present invention to provide a kiln sticker that avoids sorting and inspection.
It is another object of the present invention to provide a kiln sticker that minimizes contact and shadowing with lumber.
It is another object of the present invention provide a kiln sticker that is strong and durable.
It is a further object of the present invention to provide a kilns sticker that uses less material.
It is a further object of the present invention provide a kiln sticker that enhances the drying of wood.
It is still another object of the present invention provide a kiln sticker that avoids chipping and breaking.
These and other objects and advantages of the present invention will become apparent from a reading of the attached specification and appended claims.
The present invention is a kiln sticker that comprises an elongated body having a top surface, a bottom surface and a pair of side surfaces extending between the top surface and the bottom surface. The top surface has a first cut-out formed therein. The first cut-out extends for the entire length of the elongated body. The bottom surface has a second cut-out formed therein. The second cut-out also extends for the entire length of the elongated body. The first cut-out opens to the top surface. The second cut-out opens to the bottom surface.
The first cut-out is symmetrical with the second cut-out. The first cut-out has a width at the opening at the top surface that is greater than one half the width of the top surface. The bottom surface has a width at the opening at the bottom surface that is greater than one half the width of the bottom surface. Each of the cut-outs can have a semicircular, semi-oval, semi-elliptical, or parabolic shape.
Each of the pair of side surfaces has a first planar surface extending downwardly from the top surface and a second planar surface extending upwardly from the bottom surface. An end of the first planar surface meets an end of the second planar surface. The first planar surface angles outwardly from the top surface while the second planar surface angles outwardly from the bottom surface. A first chamfer or radius can be formed between the top surface and the first planar surface. A second chamfer or radius can be formed between the bottom surface and the second planar surface.
The top surface defines a first pair of planar shoulders at opposite sides of the first cut-out. The bottom surface defines a second pair of planar shoulders at opposite sides of the second cut-out. A first pair of planar surfaces are co-planar. The second pair of planar surfaces are also coplanar. Each of the pair of side surfaces has a generally V-shaped configuration. The elongated body has a greatest width centrally of the V-shaped configuration of the pair of side surfaces. The elongated body can be formed of a polymer, an elastomer, fiberglass, or wood.
This foregoing Section is intended to describe, with particularity, the preferred embodiments of the present invention. It is understood that modifications to these preferred embodiments can be made within the scope of the present claims. As such, this Section should not to be construed, in any way, as limiting of the broad scope of the present invention. The present invention should only be limited by the following claims and their legal equivalents.
Referring to
The first cut-out 32 will be symmetrical with the second cut-out 34. The first cut-out 32 has a width dimension at the location where the first cut-out 32 opens at the top surface 24. The width of the first cut-out is greater than one-half the entire width of the top surface 24 between side surfaces 28 and 30. Similarly, the second cut-out 34 will have a width dimension at the opening at the bottom surface 26. Once again, this width dimension of the second cut-out 34 will be greater than one-half the entire width of the bottom surface 26 as measured between side surfaces 28 and 30. It can be seen that the cut-outs 32 and 34 can be semi-circular, semi-oval, semi-elliptical, or parabolic.
The side surface 30 has a first planar surface 36 extending downwardly from the top surface 24. Side surface 30 also has a second planar surface 38 extending upwardly from the bottom surface 26. The first planar surface 36 and the second planar surface 38 will have an end meeting at line 40. Line 40 is central of the side surface 30. Side surface 28 will have a similar configuration to that of side surface 30. It can be seen that the first planar surface 36 angles outwardly and downwardly from the top surface 24. Similarly, the second planar surface 38 angles upwardly and outwardly from the bottom surface 26. The first planar surface 36 and the second planar surface 38 have a V-shaped configuration. The width of the elongated body 28 is greatest at the center of the side surfaces 22 and 30 (i.e., out at line 40).
As can be seen in
The elongated body 22 is be preferably formed of fiberglass. However, the elongated body 22 can also be formed of a polymer, an elastomer or wood. Additionally, so as to reduce cost, the elongated body 22 can be formed from recycled plastics. Ultimately, the material used for the elongated body should be able to withstand the temperatures associated with a wood drying and curing kiln. The elongated body 22 can be easily formed through an extrusion or pultrusion process. It is only necessary to extrude the symmetrical shape of the elongated body and cut the extruded material into desired lengths.
The kiln sticker 20 of the present invention has a number of unique advantages. First, each of the top surface 24 and the bottom surface 26 will minimally contact the uppermost wood panel and the lowermost wood panel between which the kiln sticker 20 is placed. As such, this effectively minimizes any “shadowing” of the wood placed upon the surfaces. The use of the cut-outs 32 and 34 facilitates the airflow and enhances the drying of wood. Since the kiln sticker 20 is formed of a synthetic material, and not formed of wood, it will become extremely difficult to damage. As such, the kiln sticker 20 can be repeatedly reused throughout the wood drying and curing processes. An important feature the present invention is the unique V-shaped configuration of the side surfaces 28 and 30. No matter how the kiln sticker 20 may land after being discharged by a conveyor belt, the V-shaped side surfaces will create a “self-righting” effect. As such, if the kiln sticker 20 should land the one of the side surfaces, the angling of the side surfaces will cause the kiln sticker to tip over to the proper orientation, such as illustrated in
The use of synthetic material, such as recycled plastic, greatly reduces the cost associated with the kiln sticker 20. Since the kiln sticker 20 is formed of a synthetic material, it will not warp, break or become damaged after repeated reuse. As such, the present invention avoids the need to replace damaged kiln stickers. Since the kiln sticker 20 is formed of a synthetic material, there is no need for continual inspection and replacement of such kiln stickers.
The top surface 24 defines a pair of planar shoulders 44 and 46. This pair of planar shoulders 44 and 46 are on opposite sides of the first cut-out 32. The bottom surface 26 defines another pair of planar shoulders 48 and 50 on opposite sides of the second cut-out 34. Planar shoulders 44 and 46 are coplanar. Similarly, planar shoulders 48 and 50 are coplanar. The planar shoulders 44, 46, 48 and 50 can have a peel ply surface thereon. As such, this provides an anti-slip feature to the kiln sticker 20 of the present invention. The planar surfaces on the side surfaces 28 and 30 would not have such an anti-slip feature since it is desirable for the side surfaces to gravitate toward the position wherein the shoulders 44 and 46 are at the top and shoulders 48 and 50 are at the bottom. This peel ply surface should have a certain degree of tackiness so as to be easily separable from the overlying an underlying courses of wood.
Side surface 28 has a first planar surface 52 and a second planar surface 54 which meet at line 56. The first planar surface 52 angles downwardly and outwardly from the first planar shoulder 44 of top surface 24. The second planar surface 54 angles upwardly and outwardly from the first planar shoulder 48 of the bottom surface 26. The ends of the planar surfaces 52 and 54 will meet at line 56. As was described hereinabove, the second side surface 30 has a first planar surface 36 and a second planar surface 38. The first planar surface 36 angles downwardly and outwardly from the second planar shoulder 46 of top surface 24. The second planar surface 38 angles upwardly and outwardly from the second planar shoulder of bottom surface 26. Ultimately, the planar surfaces 36 and 38 will meet at line 40.
The planar surfaces 36, 38, 52 and 54 will extend and angle with respect to horizontal. In the preferred embodiment of the present invention, this angle can be 76°, 78°, 80° or 82°. However, within the concept of the present invention, these angled planar surfaces can be arranged at various other angles.
In
In
The foregoing disclosure and description of the invention is illustrative and explanatory thereof. Various changes in the details of the illustrated construction can be made within the scope of the appended claims without departing from the true spirit of the invention. The present invention should only be limited by the following claims and their legal equivalents.
