AU2014200652A1 - A cover strip - Google Patents

Abstract

A cover strip to cover an elongate channel of an architectural fitting. The cover strip comprises a transversely flexible axially shrink susceptible plastics and an 5 integrally formed axially extending shrink inhibiting means, to inhibit shrinkage of the flexible plastics. The shrink resistant plastics that may be a rigid plastics that is co-extruded with the flexible plastics. Figure 3 15 Figure 4 Figure 5 Figure 6

Description

P/00/01 1 Regulation 3.2 AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT ORIGINAL TO BE COMPLETED BY APPLICANT Name of Applicant: Raven Products Pty Ltd Address for Service: A.P.T. Patent and Trade Mark Attorneys PO Box 222, Mitcham, SA 5062 Invention Title: A cover strip The following statement is a full description of this invention, including the best method of performing it known to me/us:- 2 A cover strip FIELD OF THE INVENTION This invention relates to a cover strip, and particularly to a cover strip for use with 5 an elongate architectural fitting. BACKGROUND OF THE INVENTION Architectural fittings, such as might be used to provide a seal for a door, comprise a channel, whereby fasteners are typically driven through a base of the channel, to 10 fasten the fitting in place. A cover strip is secured over the channel for aesthetic purposes to conceal the channel and the fastener in the channel, as well as to reduce the extent to which debris collects in the channel. The cover strip is usually constructed from an inexpensive plastics such as a semi 15 rigid but flexible plastics, typically PVC but other plastics are also used. One of the problems with the use of flexible cover strips, particularly if made from less expensive plastics, is they have a tendency to shrink axially. The shrinkage of the cover strip means that the ends of the channel become exposed which is aesthetically undesirable and increases the extent to which debris collects behind 20 the cover strip. While there are flexible shrink resistant plastics materials currently available, these are expensive and therefore are typically not used by manufacturers. Patent specification 2013204356 describes the use of a wedge to wedge ends of 25 the cover strip to the channel to inhibit shrinkage, however, ends of such cover strips are not always accessible and there is also a chance that the wedge dislodges or loosens the frictional engagement. Furthermore it is desirable to provide for an alternative, or additional means to prevent shrinkage of a cover strip in an economic manner. 30 For purposes of this specification the word "comprising" means "including by not limited to", and the word "comprises" has a corresponding meaning. Also a 3 reference in this specification to a document is not to be taken as an admission that the disclosure therein constitutes common general knowledge in Australia. SUMMARY OF THE INVENTION 5 In a first aspect, the invention might be said to reside in a cover strip to cover an elongate channel of an architectural fitting, the cover strip comprising a transversely flexible axially shrink susceptible plastics and an integrally formed axially extending shrink inhibiting means, to inhibit shrinkage of the flexible plastics. 10 Channels of architectural fittings such as door or window seals typically comprise side walls and a base, fasteners are driven through the base to fasten the same. The side walls extend upwardly from the base, a respective flange extends inwardly from the top of each of the side walls, and sides of the cover strips are 15 usually snap fitted underneath the flanges. Such snap fitting requires some transverse flexibility of the cover strip because the flanges typically have considerable overlap. The cover strip comprises a web to cover the open channel and preferably a respective leg depends from both elongate sides of the web, the outside of the legs are each preferably tapered from a free end to the web 20 proximal end. This configuration facilitates insertion into the channel, so that on insertion inward pressure is exerted on the web. The web is typically flexible so that on insertion it flexes usually bowing upwardly, although usually the legs are also flexible so that they can also deform inwardly on 25 insertion. The cover strip preferably further comprises a respective elongate land on top of each leg, the land being complementary to a lower surface of a respective flange, so that once the cover strip is inserted the land snaps outwardly and is captured by said lower surfaces of the respective flanges. The legs preferably extend down adjacent the base of the channel when the cover strip is 30 inserted to maintain the land adjacent the lower surface of the flange. It will be understood that legs are preferred but are not essential to the working of this invention, and in some forms of the invention there are no legs, but preferably 4 there is a respective land at a peripheral upper edge of each side of the cover strip. Where there are no legs the web is resiliently flexible transversely and preferably acts to urge a peripheral upright face of the web against internal sides of the two flanges to provide a measure of frictional engagement thereagainst. 5 Alternatively there may be provided a snap fit over the flange with a protrusion or expanded lower edge extending outwardly so that it can be forced over the flange in a snap fit fashion. There may also be provided an overhanging portion to seat on top of the flange to locate the same on the channel. 10 The shrink inhibiting means is preferably co-extruded with the shrink susceptible plastics, and may comprise rigid plastics. The shrink inhibiting means in this form is preferably at least one axially elongate strip of plastics, that resists shrinkage. The shrinkage resistant plastics may be a flexible plastics that is shrinkage resistance, however, such plastics is relatively expensive. Less expensive plastics 15 that may be used that are shrinkage resistance are rigid plastics these contain less plasticisers which is the component of the less expensive flexible plastics that makes them prone to shrinkage. The shrinkage resistant plastics may comprise the web, or may comprise one or more strips forming part of the web and extend the entire length of the cover strip. 20 Preferably the shrink resistant strip extends the entire length of the cover strip. This is also convenient because such strip will be extruded and thus the flexible plastics and the shrink resistant plastic will be co-extruded to the entire length of the strip. It will be understood however that the shrink resistant plastics need not 25 extend the entire length of the cover strip and still provide significant improvement in the extent that the cover strip shrinks. In one alternative the shrink inhibiting means may comprise a plurality of axially elongate strips each forming just a portion of the length of the cover strip. Thus 30 the plurality of elongate strips may be laterally staggered, and adjacent ones may be axially overlapping one with respect to another.

5 Alternatively the elongate strips of rigid plastic may comprise all or part of one or both legs, the web consisting of flexible shrink susceptible plastics, although in other forms of this embodiment of the invention the web may also comprise one or more axially elongate strips of rigid plastics. 5 Whilst preferred embodiments of this invention contemplate the shrink inhibiting means being a coextruded plastics strip, other forms of shrink inhibiting means may also be used. Thus, for example, glass fibres or metal strands may be embedded in the flexible plastics, to provide the inhibition to shrinkage. 10 The plastics from which the cover strip may be made may be selected from, but not limited to, polyvinyl chloride (PVC), thermoplastic vulcanizate (TPV), thermoplastic rubber (TPR), thermoplastic elastomer (TPE), ethylene propylene diene monomer (EPDM), or any other type of resiliently flexible material. 15 The principal consideration of the rigid plastics is that it reduces shrinkage of the flexible plastics and as a result less expensive flexible plastics may be used. Using one specific measure the rigid plastics may be harder than 50 Shore D, preferably harder than 55, 60, 65, and more preferably 70 Shore D or harder. The 20 flexible plastics may be less than 40 Shore D, or preferably less than 35, or 30 Shore D. In a second broad aspect the invention could be said to reside in an architectural fitting comprising an elongate member having an elongate channel comprising a 25 base through which fasteners are driven to fix the member, and two side wall extending upwardly from either side of the base defining an elongate opening of the channel, a cover strip comprising a transversely flexible axially shrink susceptible plastics and an integrally formed axially extending shrink inhibiting member, the cover strip fitted over the channel to close off the elongate opening of 30 the channel.

6 It is to be understood that the cover strip of any one form or more than one form combined of the first aspect of the invention may be used in the second aspect of the invention. 5 The architectural fitting may be a door or window seal. BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding the invention will now be described with reference to the drawings wherein: 10 Figure 1 is a transverse cross sectional view of a prior art cover strip; Figure 2 is a perspective view from above of the prior art cover strip of figure 1; 15 Figure 3 is a transverse cross section view of a first embodiment of the present invention; Figure 4 is a transverse cross section view of a second embodiment of a 20 cover strip of the present invention; Figure 5 is a transverse cross section view of a third embodiment of a cover strip of the present invention; 25 Figure 6 is a transverse cross section view of a fourth embodiment of a cover strip of the present invention; Figure 7 is a transverse cross section view of a first embodiment of an architectural fitting of the present invention; 30 Figure 8 is a perspective view of the embodiment shown in Figure 7 fitted to a door frame and acting on a door; 7 Figure 9 is a transverse cross section view of a second embodiment of an architectural fitting of the present invention; Figure 10 is a transverse cross section view of a third embodiment of an 5 architectural fitting of the present invention; Figure 11 is a transverse cross section view of a fourth embodiment of an architectural fitting of the present invention; 10 DETAILED DESCRIPTION OF THE ILLUSTRATED AND EXEMPLIFIED EMBODIMENTS There are numerous specific details set forth in the following description. However, from the disclosure, it will be apparent to those skilled in the art that modifications and/or substitutions may be made without departing from the scope 15 and spirit of the invention. In some circumstance specific details may have been omitted or enlarged so as not to obscure the invention. Similar reference characters indicate corresponding parts throughout the drawings. Figure 1 shows a prior art cover strip (1) covering a channel (2) of an architectural 20 fitting (shown in part as 3). The channel comprises an elongate base (5) and two elongate side walls (6, 7) extending upwardly from the base. A respective elongate flange (8, 9) extends inwardly from the top of each of the side walls. The channel thus comprises an upwardly facing elongate opening (11). The base comprises a locating groove (10) for locating the tip of a fastener, for example, a 25 self tapping screw, that can be driven through the base to fasten the architectural fitting. The architectural fitting is thus fastened via the base (5) of the channel, and it may as illustrated for one specific embodiment below be fitted to a door frame. The architectural fitting may alternatively be fastened to a door, window, or wall, or other part of a building. 30 The cover strip comprises a web (15) to cover the open channel and a respective leg (16, 17) depending from both elongate sides of the web. The cover strip 8 comprises a respective elongate land (18, 19) on top or each leg. The land is complementary in shape to a lower surface of a respective flange (20, 21). Figure 2 shows a perspective view of the cover strip (1). 5 The cover strip is made of a flexible plastics that is relatively inexpensive for example a PVC with a shore D measure of 30. For insertion, the cover strip is placed over the channel and the legs are squeezed toward each other so as to fit between flanges (8, 9).The web bows upwardly to accommodate the relative 10 movement of the legs. Additionally the legs can be pivoted relative to an upper portion thereof so that the free ends may be pivoted toward each other. The outer edge of the legs are tapered outwardly from a free end of the legs to the web proximal portion to facilitate this insertion. As the cover strip is inserted the lands (18, 19) are compressed but then snap outwardly when they get below the 15 downwardly facing surfaces (20, 21) of the flanges whereupon they snap outwardly. Four embodiments of cover strips according to this invention are shown in figures 3 to 6. The cover strips of these illustrated embodiment comprise two plastics, a 20 flexible shrink susceptible plastics and secondly a rigid shrink resistant plastics. The flexible plastics may be a flexible PVC (poly vinyl chloride) with a hardness of 30 Shore D, the rigid plastics may be a rigid PVE with a hardness of 70 Shore D. The two plastics in the illustrated embodiments are co-extruded, by techniques 25 well known in the art. The illustrated embodiment are shown as taking the shape of prior art cover strips. The first embodiment of the cover strip according to this invention is shown in Figure 3. In this embodiment the web (15) is made of flexible plastics to provide 30 the usual flexing of the web during insertion of the cover strip into the channel, whereas the legs (16, 17) are made of rigid plastics to provide the shrinkage resistance.

9 The second embodiment of the coverslip according to this invention is shown in Figure 4. In this embodiment the web (15) is made of rigid plastics to provide shrink resistance, whereas the legs (16, 17) are made of flexible plastics. The whilst there is considerably reduced flexibility of the web, the legs are able to flex 5 and accommodate the considerable overlap with the flanges (8,9) of the channel (1) into which they are fitted. The third embodiment of the coverslip according to this invention is shown in Figure 5. In this embodiment a rigid web insert (25) is co-extruded into the web, 10 the remainder of the web and the legs are made of flexible plastics. The fourth illustrated embodiment of the cover strip according to this invention is shown in Figure 6. In this embodiment a respective leg insert (26, 27) is co extruded into a respective leg. This embodiment provides for the transverse 15 flexibility closest to that of the original cover strip. Figures 7 through 11 show a number of architectural fittings associated with doors to which the cover strip of this invention is applicable. Figures 7 and 8 show a door seal (30) comprising a soft rubber seal (31) that is held behind an arm (32) of 20 the architectural fitting (3). A channel (2) of the architectural fitting is placed against a door frame (33) and a plurality of fasteners (one of which is shown at 34) is driven through the base (5) of the channel. The cover strip (1) which is shown as a part cutaway is fitted into the channel as described above. The soft rubber seal as can be seen in figure 8 forms a cushion between the door (38) and the 25 door frame. Figures 9 to 11 shows three other architectural fittings (3) that act as door seals, each comprising a channel (2) having a base (5) through which fasteners are driven to hold the fitting either to a door frame or door. A cover strip (1) in each 30 case covers the channel. Various features of the invention have been particularly shown and described in connection with the exemplified embodiments of the invention, however, it must be 10 understood that these particular arrangements merely illustrate and that the invention is not limited thereto and can include various modifications, which fall within the spirit and scope of the invention.

Claims (20)

1. A cover strip to cover an elongate channel of an architectural fitting, the cover strip comprising a transversely flexible axially shrink susceptible plastics and 5 an integrally formed axially extending shrink inhibiting means, to inhibit shrinkage of the flexible plastics.

2. The cover strip of claim 1 wherein the shrink inhibiting means is at least one axially elongate strip of plastics. 10

3. The cover strip of claim 2 wherein the shrink resistant plastic is a rigid plastics.

4. The cover strip of claim 2 wherein the shrinkage resistant plastics is a 15 flexible plastics.

5. The cover strip of any one of claims 2 to 4 wherein the shrink resistant plastics is co-extruded with the shrink susceptible plastics. 20

6. The cover strip of any one of claims 1 to 5 comprising a web to cover the open channel and a respective leg depends from both elongate sides of the web.

7. The cover strip of claim 6 wherein the shrinkage resistant plastics comprises all of the web. 25

8. The cover strip of claim 6 wherein the shrink resistant plastics comprises one or more strips forming part of the web.

9. The cover strip of any one of claims 2 to 8 wherein the shrink resistant 30 strips extend the entire length of the cover strip. 12

10. The cover strip of any one of claims 2 to 9 wherein the elongate strips of rigid plastic comprise all or part of one or both legs, the web consisting of flexible shrink susceptible plastics. 5

11. The cover strip of claim 3 wherein the rigid plastics has a hardness of greater than 50 shore D.

12. The cover strip of any one of claims 2 to 11 wherein the flexible plastics has a hardness of less than 40 shore D. 10

13. An architectural fitting comprising an elongate member having an elongate channel comprising a base through which fasteners are driven to fix the fitting, and two side walls extending upwardly from either side of the base defining an elongate opening of the channel, a cover strip comprising a transversely flexible 15 axially shrink susceptible plastics and an integrally formed axially extending shrink inhibiting means, the cover strip fitted over the channel to close off the elongate opening of the channel.

14. The architectural fitting of claim 13 wherein the shrink inhibiting means is at 20 least one axially elongate strip of plastics.

15. The architectural fitting of claim 14 wherein the shrink resistant plastic is a rigid plastics. 25

16. The architectural fitting of any one of claims 14 to 15 wherein the shrink resistant plastics is co-extruded with the shrink susceptible plastics.

17. The architectural fitting of any one of claims 13 to 16 wherein the channels comprises side walls and a base, fasteners being driven through the base to fix 30 the same, the side walls extend upwardly from the base, a respective flange extends inwardly from the top of each of the side walls, and sides of the cover strips are snap fitted underneath the flanges, said cover strip comprising a web to cover the open channel. 13

18. The architectural fitting of any one of claims 14 to 17 wherein a respective leg depends from both elongate sides of the web, the outside of the legs are each preferably tapered from a free end to the web proximal end. 5

19. The architectural fitting of either claim 14 or 18 wherein the cover strip further comprises a respective elongate land on top of each leg, the land being complementary to a lower surface of a respective flange, so that once the cover strip is inserted the land snaps outwardly and is captured by said lower surfaces to 10 the respective flanges.

20. The architectural fitting of any one of claims 13 to 19 wherein the legs extend down adjacent the base of the channel when the cover strip is inserted to maintain the land adjacent the lower surface of the flange. 15