SEALING STRIP The present invention relates to sealing strips intended to be arranged on wings, i.e. swingable, slidable or otherwise movable members such as doors or windows, for closing an opening, or parts co-operating with such wings. The sealing strips are primarily intend for the purpose of sealing or insulating against cold, heat, draught, wind, airborne pollutants, vermin, but may also be used for vibration dampening or sound insulation. Although the sealing strips are primarily intend to be used in connection with wings in buildings, such as doors or windows, it may also be used in vehicles, machines, white goods, fan installations etc. In particular, the present invention relates to an elongate elastomeric sealing strip comprising a longitudinally extending sealing member that is integrally associated with an essentially planar base section, the sealing member having a hollow cross-section profile and having a wall portion defined by an external boundary and an internal boundary, the boundaries being essentially parallel, said hollow cross-sec- tion profile being symmetric around a perpendicular to said base section, which perpendicular crosses the width of said base section at a point equidistant between the ends of the base section width.
Sealing strips of this general kind are previously known to quite some extent in the art. For instance, sealing strips with cross-sections or profiles generally resembling to a capital "D" is presently used as draught or wind excluders for windows and doors. The straight portion of the D profile serves to anchor the sealing strip to the wing or the frame, while the curved portion provides the main part of the actual sealing.
It would be desirable to be able to provide an elongate elastomeric sealing strip of said general kind, which sealing strip provides for improved sealing properties while not requiring increased elastomeric raw material per produced length unit of the sealing strip, or, expressed in an alternative way, to be able to provide such a sealing strip that provides for comparable sealing properties while requiring less elastomeric raw material per produced length unit of the sealing strip. It would in ' particular be desirable to provide an elongate elastomeric sealing strip that provides such sealing properties regarding draught and/or wind exclusion in relation to door and windows in buildings.
The problem to be solved by the present invention is to provide such an elongate elastomeric sealing strip.
This problem is solved by an elongate elastomeric sealing strip, one general embodiment of which is defined by appended claim 1. More particularly, this general embodiment comprises an elongate elastomeric sealing strip comprising a longitudinally extending sealing member that is integrally associated with a base section, said sealing member having a hollow cross-section profile and having a wall portion defined by an external boundary and an internal boundary, said boundaries being essentially parallel, and said base section being essentially planar; said hollow cross-section profile being symmetric around a perpendicular to said base section, said perpendicular crossing the width of said base section at a point located equidistantly between the ends of the base section width, where said sealing member comprises two integrally associated flanges that are thinner than said wall portion; said flanges protrude outwards from said wall portion at angles that diverge upwards from said perpendicular; said flanges extend, when the sealing strip is in an unladened state, beyond an upper tangential line to the sealing members, which upper tangential line is parallel to said planar base section.
The sealing member comprises a space defined by the wall portion and the base section. In turn, the wall portion is defined, in cross-section, by two essen- tially parallel wall contours that are continuously curved and joined to define a single area, such as, for instance, a circle, an oval, or an egg shape.
In a preferred embodiment of the invention said sealing member is essentially circular in cross-section. The flanges may protrude along radiuses of said circular cross-section. In one embodiment of the invention the wall thickness of the flanges decrease in the protruding direction.
The inventive sealing strip is preferably made of EPDM (Ethylene- Propylene-diene terpolymer), EPM (Ethylene-Propylene Copolymer), SBR (Styrene- Butadiene Rubber), PVC (Polyvinyl chloride), EVA (Ethylene Vinyl acetate Co- polymer), or thermoplastic elastomer.
In a preferred embodiment of the invention the sealing strip is made of EPDM.
The inventive sealing strip is preferably made of cellular rubber, such as expanded, foamed, or sponge rubber, preferably expanded rubber as the closed cellular structure of expanded rubber makes it impervious to water.
The inventive sealing strips may be provided with a self-adhesive layer for mounting. They may also be tacked or glued into place by means of separately provided adhesive. Alternatively, they may also be stapled or pinned to the substrate surface.
Preferably, the annular sealing member has an essentially circular cross- section, having a diameter of from about 3 to 25 mm, preferably from about 3.5 to 12 mm, in particular from about 4 to 9 mm.
The wall thickness of the sealing member is may be from about 1 to 4 mm, preferably from about 1 to 2 mm, in particular from about 1 to 1.5 mm.
The planar base section may have a width of from about 4 to 25 mm, preferably from about 5 to 15 mm, in particular from about 8 to 10 mm. The flanges may protrude outwards from the sealing member at an angle of from about 0 to 90 degrees, preferably from about 30 to 60 degrees, in relation to the bottom surface.
The sealing strip according to the present invention provides numerous advantages, in particular regarding sealing properties, but also regarding the produc- tion of the sealing strip.
The flange provides for improved flexibility of the sealing strip in relation to unevenness in the confronting surfaces between which it is applied. This means that the sealing properties of the present sealing strip in relation to varying clearances between confronting surfaces is improved in relation to prior art sealing strips. In addition, the relative small wall thickness of the flange provides for even more improved flexibility of the sealing strip in relation to such unevenness. The sealing strip of the invention provides better sealing characteristics at lower compressions than do the prior art sealing strips. The sealing properties are particularly improved for situations where the system of the sealing strip and the confronting surfaces is subjected to wind or draught, especially in situations where the confronting surfaces are put in motion in relation to each other. The present sealing strip leaves little or no opportunities for error in application (i.e. the sealing strip is more or less what is
occasionally referred to as "foolproof), due to the symmetric design, as will be appreciated by the artisan.
The sealing strip may be manufactured by extruding a continuous length of elastomeric material from a conventional extruder, which includes a die formed in the shape of the cross-section of the sealing strip. Uncured polymer is fed into the extruder, which forces the material out from the extruder in the desired configuration. The uncured, extruded sealing strip is drawn through a vulcanizer in a conventional manner. The sealing strip will cure due to the temperature of the vulcanizer. As the sealing strip proceeds from the vulcanizer, it will be cut into desired lengths and then processed as appropriate for each application.
Multiple sealing strips may be extruded simultaneously and in parallel through one die; this is because the width of the cross-section of the present sealing strip is well defined, without any parts protruding in lateral direction.
As the present sealing strip require less material than comparable prior art sealing strips, the curing time will be considerably shorter, and thus the energy consumption per produced length unit will be lower. The reduced material and energy consumption implies reduced environmental impact.
Additional objects, features and advantages will be apparent in the written description that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is side elevational view of one embodiment of the sealing strip of the invention mounted on a first surface and prior to contacting a second confronting surface; and
FIG. 2 is a view similar to FIG. 1 showing the operative position in which the second confronting surface has contacted the sealing strip;
Referring to FIG. 1, sealing strip 10 has a base 20 that extends the full length of the sealing strip. The base 20 has a bottom surface 22, the width of which is
adapted to separately provided adhesive strips for bonding sealing strip 10 to the first 80 of two confronting surfaces.
Sealing strip 10 has a deforming sealing member, designated generally as 15, which protrudes outwardly from base 20 for sealing contact with the second of the confronting surfaces (90 in FIG. 2). Sealing member 15 includes a wall portion 30 integrally formed with base 20, which wall 30 defines, in the depicted embodiment, a circular hollow interior 25. Wall portion 30 is defined by an external boundary 35 and an internal boundary 40, which boundaries are parallel.
The hollow cross-section profile is symmetric around a perpendicular 45 to base section 20. The perpendicular 45 crosses the width of base section at a point located equidistantly between the ends 60,65 of the base section width.
Longitudinally extending flanges 50,55 protrude outwards from sealing member 15, and extends along the entire length of the sealing strip 10. As seen in Fig 1, flanges 50,55 protrude, when the sealing strip is in an unladened state, above the upper tangential line of annular sealing member 15.
As seen in Fig. 2, flanges 50,55 are deformed toward the first 80 of the confronting surfaces when the second confronting surface 90 is brought into contact with and pressed against sealing strip 10. In this situation an air duct 100 is defined between flanges 50,55 and the second confronting surface 90. The air duct 100 pro- vides thermal insulation in addition to that provided by the air in the circular hollow interior 25, resulting in overall excellent sealing and insulation properties.