US 3535824 A
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Description (OCR text may contain errors)
G. KESSLER 3,535,824
ABRASION-RESISTANT RIGID-FLEXIBLE WEATHERSTRIP Oct. 27, 1970 Filed March 2. 1967 FIG. 2.
Adhesive Powdered Hard Resin ExTrusion Die Flexible Vinyl Rigid Vinyl INVENTOR Gerald Kessler BY mm ATTORNEY United States Patent 3,535,824 ABRASION-RESISTANT RIGID-FLEXIBLE WEATHERSTRIP Gerald Kessler, 388 Cranberry Road, Youngstown, Ohio Filed Mar. 2, 1967, Ser. No. 620,036 Int. Cl. B32]; 7/02, 9/00 U.S. Cl. 49-488 1 Claim ABSTRACT OF THE DISCLOSURE In the art of Weatherstripping, i.e., protecting interiors from the access of exterior weather at the joints formed by movable doors and windows, it is known to use a strip of flexible material to seal the edges of doors and windows, and it is also known to provide on the surface of the flexible material, where it engages a surface which must be moved when the door or window is opened or closed, a layer of material such as velvet pile, felt, or other soft and flexible material which both helps to maintain a good seal and tends to reduce sliding friction, particularly where the door or window is opened or closed by sliding motion. Furthermore, a rigid base must usually be provided for the Weatherstrip material, whereby it can be properly fastened or attached to one of the two surfaces which are to be sealed, the flexible portion and covering material extending toward and in contact with the other of said surfaces. Since the requirements for the base, flexible strip, and surface material are different, different materials are usually employed for this, which adds to the expense of the Weatherstripping. For example, the base is often made of a metal backing member into which a flexible plastic strip is inserted, and the external coat of pile or flock material is applied to the plastic at the region where it engages the other surface to be sealed.
It is a major object of the present invention to provide a unitary Weatherstrip material which can be extruded in plastic form so that it can be manufactured very cheaply, yet which will be satisfactory in operation both with respect to a low coefficient of friction and with respect to abrasion resistance.
According to the invention, known dual-extrusion techniques are used to extrude a compound strip having a rigid plastic base strip for attachment to one of two surfaces to be sealed, and a flexible plastic Weatherstrip attached along one edge to the rigid plastic strip so that it can extend out toward the opposite surface from that on which the base is mounted in order to provide a weather seal between the two surfaces. Since these two surfaces are often relatively slidable, in the course of opening and shutting the door or window, a considerable amount of wear is imposed upon the Weatherstrip; furthermore, if a Weatherstrip has a surface with a relatively high coefficient of friction, this renders the operation of opening or closing the door or window very difficult. It is therefore desirable to impose between the Weatherstrip and said opposite surface an additional layer of material, and for this purpose felt, flocking, or velvet pile is often employed. In accordance with the present invention, a similar effect is provided by instead coating the sealing surface of the flexible Weatherstrip, where it is ice to engage the surface to be protected, with a thin layer of adhered-on particles of a harder material, such as powdered or ground-up hard plastic, which provides greatly increased abrasion resistance, and, particularly after a short period of use, also provides greatly reduced friction between the two surfaces.
The specific nature of the invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawing, in which:
FIG. 1 is a transverse sectional view of a Weatherstrip according to the invention in a typical use situation;
FIG. 2 is a perspective view of a section of weatherstrip according to the invention on an enlarged scale, showing the details of its construction; and
FIG. 3 is a highly schematic flow chart showing one method of making the Weatherstrip of the invention.
Referring first to FIG. 2, the Weatherstrip comprises a base portion 2 of extruded rigid plastic having sufficient mechanical strength to support the Weatherstrip for attachment to any surface to be sealed, such as a door jamb, window sill, or edge of a door or window frame. This connection may be made in any desired way, as by gluing the strip to the edge, nailing it, or, as is commonly done, by providing a special groove as shown in FIG. 1 into which the rigid portion 2 of the Weatherstrip may he slid. Extending away from the strip 2, at a fairly acute angle, typically in the order of is a flexible Weatherstrip 3, which is joined at one edge 4 to the rigid Weatherstrip along a longitudinal line lying between the two edges of the rigid Weatherstrip, usually along the center line thereof. The two strips are firmly attached together, preferably by a combination of mechanical interlocking as shown at 4, and thermal fusion, resulting from the manufacture of the double strip by well-known dual-extrusion techniques whereby both strips are extruded from a single die head to form a composite strip as shown, the two strips being thermally welded together at the region of junction due to the heat and pressure employed in the extrusion process. Techniques for simultaneously extruding two different types (or colors) of plastic from a single extrusion die to form a single combined extruded product are well known in this art.
Along the upper side of the free edge of flexible strip 3 there is a band 6 of hard powdered granules, preferably hard resin powder, which are adhered to the surface of the flexible strip 3 by means of a layer of adhesive 7, which may be applied as shown below.
FIG. 1 shows the Weatherstrip of FIG. 2 in a typical use situation, where it is inserted in a suitable slot in the edge of a window or door frame 8, so that the flexible strip 3 extends toward and in contact with the opposite edge of a door or window 9. The closure may be either of the hinged or sliding type, but especially in the case where it is the sliding type, and is opened and closed by sliding motion along the edge of Weatherstrip 3, it will be apparent that both friction and wear will be minimized due to the layer of hard material 6 which forms the actual contact surface between the two relatively movable elements. In modern practice, the door or window and their frames are commonly made of extruded metal such as aluminum, or in some cases are also made of hard and rigid plastic, having a fairly smooth exterior surface, against which the individual particles of the powdered layer 6 quickly become somewhat polished in use to provide a very satisfactory contact surface having much less friction than the soft material of the strip itself would provide, and also having a much higher resistance to wear and abrasion. The actual contact surface being made up of individual particles, is not rigid, but can readily flex to conform to minor irregularities of the surface to be sealed, thereby providing excel- 3 lent sealing engagement between the Weatherstrip and the surface to be protected. Furthermore, this type of weatherstrip is not affected by moisture or atmospheric conditions.
FIG. 3 shows in schematic form one manner in which the above Weatherstrip can be made. The flexible vinyl material in container 9 and the rigid vinyl material in container 11 are both fed to a single die head 12 which is properly shaped to produce the combination of the above-described strips 2 and 3. This combined strip is passed under a roller 13 supplied with adhesive from a suitable storage and feeding receptacle 14, so that it coats the upper edge of strip 3 with a thin layer of a suitable adhesive. Further down the line, there is deposited upon this thin layer of adhesive a strip or layer of hard resin powder 6, from a suitable container and distributor 17, thus completing the finished product. The finished strip is thereafter cut up into suitable lengths, or wound up on coils as desired. It will be understood that the small sectional views above the flow line 18 are taken transversely to the flow line, in order to illustrate schematically the various steps of the process. The actual strip, of course, moves in the direction of its length, and is treated during this motion in the sequence shown.
While the surfacing granules 6 are described as granules of hard resin powder, it will be apparent that any other suitable surfacing material may be used which has the desirable characteristics. The chief point is to provide a hard and durable contact surface on a flexible strip, which will have the flexibility of the underlying strip and the durability and low-friction characteristics at the contact area of a much harder material. It is also apparent that the shape of the Weatherstrip may be modified to suit particular needs without departing from the spirit of the invention.
It will be apparent that the embodiments shown are only exemplary and that various modifications can be 4 made in construction and arrangement within the scope of the invention as defined in the appended claim.
1. (a) An extruded all-plastic Weatherstrip having a longitudinally extending base portion of rigid plastic material, of sufficient mechanical strength to support the Weatherstrip in a slot below a surface to be sealed, (b) a longitudinally extending strip of flexible plastic material having two edges and two sides, and fused along one of said edges to said base portion, (0) the other edge of said strip being free to flex, (d) at least one of said sides near said free edge having an adhered surface layer of small particles of hard, abrasion-resistant plastic material having a low coefficient of friction, (e) said rigid base portion being a flat strip having two edges and two sides, the flexible strip being attached to the rigid strip along the line between the two edges, leaving both edges of the rigid strip free for insertion into a slot as the sole support of the Weatherstrip.
References Cited UNITED STATES PATENTS 2,188,815 1/1940 Murphy. 2,734,238 2/l956- Clapp 49-494 2,884,668 5/ 1959 Harris et a1.
3,079,653 3/1963 Cornell 49-469 XR 3,359,688 12/1967 Konolf 49-490 FOREIGN PATENTS 575,060 3/ 1958 Italy.
ROBERT F. BURNETT, Primary Examiner W. A. POWELL, Assistant Examiner US. Cl. X.R.