Patent Application
20160237737
Pile weatherstripping is inserted into slots in windows and/or door frames and provides a barrier to prevent the infiltration and/or exfiltration of air, water, insects, etc. A backing strip or backer of the pile weatherstripping is inserted to a corresponding slot in the frame during assembly. Too much friction between the backer and the slot can make insertion (and subsequent removal) of the weatherstripping difficult or impossible. Too little friction can result in movement between the base and the slot, which may result in the weatherstripping sliding out of the slot, causing a disruption to window manufacturing.
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features or essential features of the claimed subject matter, is not intended to describe each disclosed embodiment or every implementation of the claimed subject matter, and is not intended to be used as an aid in determining the scope of the claimed subject matter. Many other novel advantages, features, and relationships will become apparent as this description proceeds. The figures and the description that follow more particularly exemplify illustrative examples.
In one aspect, the technology relates to a pile weatherstrip having: an elongate base portion having a base portion width and a base portion amplitude greater than the base portion width; and a pile extending from a central portion of the elongate base portion. In an embodiment, the base portion has a first deformation on a first side of the pile and a second deformation on a second side of the pile, and wherein the amplitude is measured from an outer limit of the first deformation to an outer limit of the second deformation. In another embodiment, the first deformation has a first deformation width extending from proximate the pile to the outer limit of the first deformation. In yet another embodiment, the first deformation has a first deformation length extending along the elongate base portion, wherein the first deformation length is greater than the first deformation width. In still another embodiment, a pile support extending from the elongate base portion, wherein the pile is bordered on at least one side by the pile support, and wherein the first deformation contacts the pile support.
In another embodiment of the above aspect, the base portion amplitude is about 120% to about 200% of the base portion width. In an embodiment, the first deformation length is about 100% to about 200% of the first deformation width.
In another aspect, the technology relates to a weatherstrip having: an undulating elongate base portion; and a pile extending from a central portion of the undulating elongate base portion. In an embodiment, the undulating elongate base portion has an effective width greater than an actual width of the undulating elongate base portion. In another embodiment, the undulating elongate base portion has a non-linear centerline. In yet another embodiment, the undulating elongate base portion has a plurality of deformations, wherein outer limits of the plurality of deformations define an amplitude of the undulating elongate base portion. In still another embodiment, the undulating elongate base portion undulates laterally. In another embodiment, the pile extends substantially orthogonal from the undulating elongate base portion.
In another aspect, the technology relates to a weatherstrip having: a substantially uniform elongate base portion having: a first edge; a second edge; and a first deformation formed in a portion of the first edge, wherein a portion of the second edge opposite the first deformation has a curvature. In an embodiment, a second deformation formed in a portion of the second edge, wherein a portion of the first edge opposite the second deformation has a curvature. In another embodiment, a pile extends from the substantially uniform elongate base portion and a pile director bordering the pile. In yet another embodiment, the deformation at least partially contacts the pile director. In still another embodiment, the deformation has a textured surface of the substantially uniform elongate base portion.
In another embodiment of the above aspect, the textured surface is formed in an upper surface of the substantially uniform elongate base portion. In an embodiment, a fin is disposed within the pile.
Retention technologies utilized in conjunction with pile or other weatherstrips help retain the weatherstrip in the t-slot of a window extrusion. The retention force results from contact and interference between the backing strip of the weatherstrip and the outer walls of the t-slot (typically the outer walls that define the width dimension). It is desirable that the weatherstrip display sufficient retention force so the weatherstrip does not slide out of the slot during window manufacturing processes. However, retention forces that are too high can cause other problems. For example, if the interference is too high, the weatherstrip may not be easily insertable into the t-slot. Once inserted, however, due to differences in material properties, the window frame extrusion and weatherstrip (namely, the backing strip thereof) expand and contract at different rates. As such, if the weatherstrip is held too firmly in the t-slot, the weatherstrip may be damaged as the window frame expands and contracts. Additionally, it is often necessary to remove the weatherstrip after manufacture to replace a damaged weatherstrip. As such, easy removal of the weatherstrip is also desirable. The technologies described herein can be used to retain weatherstrips utilizing pile, foam profiles, rigid plastic profiles, etc., in t-slots formed in door or window frames. For clarity, however, the technologies will be described in the context of pile weatherstrips.
Prior retention technologies incorporated into weatherstrips include those depicted and described in U.S. Pat. No. 5,438,802, the disclosure of which is hereby incorporated herein by reference herein in its entirety. These technologies include the formation of so-called “nubbins” in the weatherstrip base. The nubbin of U.S. Pat. No. 5,438,802 is described as a compression of material of the backing strip, which causes a circular, projecting surface to be formed along the edge of the backing strip. The presence of the nubbin purportedly restrains the backing strip in a T-slot of a window frame. Alternative technologies include circular or curved distortions that are formed by punching holes along the edges of the backing strip. In another example, hemispherically-shaped dimples can be formed along an underside of the backing strip. Another example depicts abrasions along the outer edge of the backing strip that form flaps. However, it has been determined that the above-described prior art do not function desirably when the weatherstrip is inserted into a T-slot of a window frame extrusion.
Further discoveries have been made in the field of pile weatherstripping that have resulted in significantly increased performance. It has been discovered that a number of factors can be used to influence the retention performance of weatherstrips. These factors are described in the context of
Various factors may influence the amplitude A of the weatherstrip 200. Such factors include the size and shape of the deformations or tabs (e.g., 218, 220, 222, and so on), amount of tab projection beyond the edge of the backing strip 202, width W of the backing strip 202, the space S between tabs, and the included angle α along the edge of the backer 202 at the intersection of each tab 218, 220, 222, and so on. The amplitude A, in one example, is the dimension that represents total lateral space that the weatherstrip 200 occupies. Further, the factors that may influence the insertion, retention, and extraction forces include the number of tabs in contact with the t-slot per unit of length, the shape and size of the tabs, the backing strip 202 thickness and flatness, curvature of the backing strip 202 that results in spring pressure, amplitude A, which creates and undulating or zig-zag backing strip 202, and material surface finish.
When forming the deformations or tabs in the backing strip, punches that are perpendicular to the backer may increase the likelihood of creating an angular offset, zig-zag, and undulating form in the lateral direction of the backing strip. Due to the presence of the pile fibers, however, an embossing wheel mounted on the vertical plane would be likely to capture and distort the pile fibers. An embossing wheel mounted parallel to the backing strip has minimal positive effect on the amplitude A of the zig-zag effect. It has been discovered that an embossing wheel mounted at approximately 45 to 60 degrees from horizontal has an acceptable impact on the amount of amplitude generated.
The backing strip temperature during tab formation may be another relevant factor. Residual heat initially generated in the pile weatherstrip manufacturing process as the pile is welded to the backing strip may have a positive effect on the amount of offset generated by the embossing tool. The warm center portion of the backing strip may help the offsetting process due to the discovery that disruption of the pile director facilitates the linear distortion of the edge that results in an angular lateral undulation having an amplitude.
Disruption of the pile director has been discovered as another factor to facilitate the undulation of the backing strip.
Referring again to
T-slots commonly used in window manufacture have nominal widths between about 0.205″ to about 0.215″. In the examples, below, six-foot lengths were tested. It has been determined that removal forces of between about 0.7 pounds/linear foot and about 1.5 lb/lf are desirable. Removal forces of between about 0.7 lb/lf and about 1.0 lb/lf may be more desirable. Lower removal forces may result in the weatherstrip sliding out of the t-slot during window manufacture. Higher forces may prevent the weatherstrip from being removed.
A number of examples consistent with the teachings herein were made and tested. Table 1 presents the test results for a number of examples and includes the t-slot width T, backing strip amplitude A, tab spacing S, and removal force. In all cases, the deformations extend to and touch the pile director as described above. This results in the depicted amplitude. In all examples, six-foot lengths of weatherstrips were utilized.
The results from Table 1 are indicative of the improved performance of the weatherstrips utilizing the undulating backing strip technologies described herein. The average result for test samples A-1 through A-5 is within the desirable 0.7-1.5 lb/lf range, while average result for test samples C-1 through C-5 is within the desirable 0.7-1.0 lb/lf range. It is believed that the test results for samples B and D may be improved by, e.g., adjusting the spacing S of the deformations and/or adjusting the size of the deformations. Other modifications consistent with the disclosure herein may also be made.
Methods of manufacturing a pile weatherstrip are described generally in U.S. Pat. No. 7,419,555, the disclosure of which is hereby incorporated herein in its entirety. The deformed and/or embossed pile weatherstrip technologies described further herein may be performed continuously on weatherstrip downstream of the processes described in the above-referenced patent, prior to a reel-up unit that packages the weatherstrip for storage and delivery. Deformation/embossing may be performed as the base portion of the weatherstrip cools (e.g., while still slightly molten). Linear speed of the weatherstrip can be approximately 45 to 60 feet per minute during manufacture. The deformation or embossing unit speed can be driven and timed independently from the machine that manufactures the pile weatherstrip. Alternatively, the embossing unit can be timed with traditional loop-control techniques using a “dancer arm” or Sona-trol™ sensing system to regulate and coordinate the speed of the embossing unit to the pile weatherstrip manufacturing machine. Alternatively, the weatherstrip may be deformed once the base portion has substantially cooled (e.g., at a facility remote from the where the weatherstrip was manufactured).
While there have been described herein what are to be considered exemplary and preferred embodiments of the present technology, other modifications of the technology will become apparent to those skilled in the art from the teachings herein. The particular methods of manufacture and geometries disclosed herein are exemplary in nature and are not to be considered limiting. It is therefore desired to be secured in the appended claims all such modifications as fall within the spirit and scope of the technology. Accordingly, what is desired to be secured by Letters Patent is the technology as defined and differentiated in the following claims, and all equivalents.
This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62/116,228, filed, Feb. 13, 2015, the disclosure of which is hereby incorporated by reference herein it its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62116228 | Feb 2015 | US |
